diff --git a/Code/Network/RKHTTPRequestOperation.h b/Code/Network/RKHTTPRequestOperation.h
index a47d40c1..dca1e925 100644
--- a/Code/Network/RKHTTPRequestOperation.h
+++ b/Code/Network/RKHTTPRequestOperation.h
@@ -21,17 +21,34 @@
 #import "AFNetworking.h"
 #import "AFHTTPRequestOperation.h"
 
-// TODO: AFNetworking should expose the default headers dictionary...
+// Expose the default headers from AFNetworking's AFHTTPClient
 @interface AFHTTPClient ()
 @property (readonly, nonatomic) NSDictionary *defaultHeaders;
 @end
 
-// NOTE: Accepts 2xx and 4xx status codes, application/json only.
-// TODO: May want to factor this down into another more specific operation subclass to generalize the behavior
+/**
+ The `RKHTTPRequestOperation` class is a subclass of `AFHTTPRequestOperation` for HTTP or HTTPS requests made by RestKit. It provides per-instance configuration of the acceptable status codes and content types and integrates with the `RKLog` system to provide detailed requested and response logging. Instances of `RKHTTPRequest` are created by `RKObjectRequestOperation` and its subclasses to HTTP requests that will be object mapped. When used to make standalone HTTP requests, `RKHTTPRequestOperation` instance behave identically to `AFHTTPRequestOperation` with the exception of emitting logging information.
+ */
 @interface RKHTTPRequestOperation : AFHTTPRequestOperation
 
-// We allow override of status codes and content types on a per-request basis
-@property (nonatomic, strong) NSIndexSet *acceptableStatusCodes; // Default nil: means defer to class level
-@property (nonatomic, strong) NSSet *acceptableContentTypes;     // Default nil: means defer to class level
+///------------------------------------------------------------
+/// @name Configuring Acceptable Status Codes and Content Types
+///------------------------------------------------------------
+
+/**
+ The set of status codes which the operation considers successful.
+ 
+ **Default**: nil
+ */
+@property (nonatomic, strong) NSIndexSet *acceptableStatusCodes;
+
+/**
+ The set of content types which the operation considers successful.
+ 
+ The set may contain `NSString` or `NSRegularExpression` objects.
+ 
+ **Default**: nil
+ */
+@property (nonatomic, strong) NSSet *acceptableContentTypes;
 
 @end
diff --git a/Code/Network/RKHTTPRequestOperation.m b/Code/Network/RKHTTPRequestOperation.m
index 5e498a4f..3ab16400 100644
--- a/Code/Network/RKHTTPRequestOperation.m
+++ b/Code/Network/RKHTTPRequestOperation.m
@@ -22,6 +22,7 @@
 #import "RKLog.h"
 #import "lcl.h"
 #import "RKHTTPUtilities.h"
+#import "RKMIMETypes.h"
 
 // Set Logging Component
 #undef RKLogComponent
@@ -112,26 +113,14 @@
 
 @implementation RKHTTPRequestOperation
 
-// RestKit will attempt to parse information about failed client errors from the payload
-+ (NSIndexSet *)acceptableStatusCodes
+- (BOOL)hasAcceptableStatusCode
 {
-    NSMutableIndexSet *statusCodes = [NSMutableIndexSet new];
-    [statusCodes addIndexesInRange:RKStatusCodeRangeForClass(RKStatusCodeClassSuccessful)];
-    [statusCodes addIndexesInRange:RKStatusCodeRangeForClass(RKStatusCodeClassClientError)];
-    return statusCodes;
-}
-
-+ (NSSet *)acceptableContentTypes
-{
-    return [NSSet setWithObject:@"application/json"];
-}
-
-- (BOOL)hasAcceptableStatusCode {
     return self.acceptableStatusCodes ? [self.acceptableStatusCodes containsIndex:[self.response statusCode]] : [super hasAcceptableStatusCode];
 }
 
-- (BOOL)hasAcceptableContentType {
-    return self.acceptableContentTypes ? [self.acceptableContentTypes containsObject:[self.response MIMEType]] : [super hasAcceptableContentType];
+- (BOOL)hasAcceptableContentType
+{
+    return self.acceptableContentTypes ? RKMIMETypeInSet([self.response MIMEType], self.acceptableContentTypes) : [super hasAcceptableContentType];
 }
 
 #pragma mark - NSURLConnectionDelegate methods
diff --git a/Code/Network/RKObjectRequestOperation.m b/Code/Network/RKObjectRequestOperation.m
index ae74753c..d9f6d4b2 100644
--- a/Code/Network/RKObjectRequestOperation.m
+++ b/Code/Network/RKObjectRequestOperation.m
@@ -20,16 +20,28 @@
 
 #import "RKObjectRequestOperation.h"
 #import "RKResponseMapperOperation.h"
+#import "RKMIMETypeSerialization.h"
 
 // Set Logging Component
 #undef RKLogComponent
 #define RKLogComponent lcl_cRestKitNetwork
 
-static inline NSString * RKDescriptionForRequest(NSURLRequest *request)
+static inline NSString *RKDescriptionForRequest(NSURLRequest *request)
 {
     return [NSString stringWithFormat:@"%@ '%@'", request.HTTPMethod, [request.URL absoluteString]];
 }
 
+static NSIndexSet *RKObjectRequestOperationAcceptableMIMETypes()
+{
+    static NSMutableIndexSet *statusCodes = nil;
+    if (! statusCodes) {
+        statusCodes = [NSMutableIndexSet indexSet];
+        [statusCodes addIndexesInRange:RKStatusCodeRangeForClass(RKStatusCodeClassSuccessful)];
+        [statusCodes addIndexesInRange:RKStatusCodeRangeForClass(RKStatusCodeClassClientError)];
+    }
+    return statusCodes;
+}
+
 @interface RKObjectRequestOperation ()
 @property (nonatomic, strong, readwrite) RKHTTPRequestOperation *requestOperation;
 @property (nonatomic, strong, readwrite) NSArray *responseDescriptors;
@@ -57,6 +69,8 @@ static inline NSString * RKDescriptionForRequest(NSURLRequest *request)
         self.request = request;
         self.responseDescriptors = responseDescriptors;
         self.requestOperation = [[RKHTTPRequestOperation alloc] initWithRequest:request];
+        self.requestOperation.acceptableContentTypes = [RKMIMETypeSerialization registeredMIMETypes];
+        self.requestOperation.acceptableStatusCodes = RKObjectRequestOperationAcceptableMIMETypes();
         
         // Initialize avoidsNetworkAccess based on caching preferences
         switch(self.request.cachePolicy) {
@@ -69,7 +83,6 @@ static inline NSString * RKDescriptionForRequest(NSURLRequest *request)
                 self.avoidsNetworkAccess = YES;
                 break;
         };
-        // TODO: set acceptable MIME Types based on available serializations?
     }
     
     return self;
diff --git a/Code/Support/RKMIMETypeSerialization.h b/Code/Support/RKMIMETypeSerialization.h
index d6ba4e77..4211920c 100644
--- a/Code/Support/RKMIMETypeSerialization.h
+++ b/Code/Support/RKMIMETypeSerialization.h
@@ -70,6 +70,13 @@
  */
 + (Class<RKSerialization>)serializationClassForMIMEType:(NSString *)MIMEType;
 
+/**
+ Returns a set containing the string values for all MIME Types for which a serialization implementation has been registered.
+ 
+ @return An `NSSet` object whose elements are `NSString` values enumerating the registered MIME Types.
+ */
++ (NSSet *)registeredMIMETypes;
+
 ///-----------------------------------------------------------------------------
 /// @name Serializing and Deserializing Content by MIME Type
 ///-----------------------------------------------------------------------------
diff --git a/Code/Support/RKMIMETypeSerialization.m b/Code/Support/RKMIMETypeSerialization.m
index 2b7c353e..9843aea6 100644
--- a/Code/Support/RKMIMETypeSerialization.m
+++ b/Code/Support/RKMIMETypeSerialization.m
@@ -58,15 +58,7 @@
 
 - (BOOL)matchesMIMEType:(NSString *)MIMEType
 {
-    if ([self.MIMETypeStringOrRegularExpression isKindOfClass:[NSString class]]) {
-        return [[MIMEType lowercaseString] isEqualToString:[self.MIMETypeStringOrRegularExpression lowercaseString]];
-    } else if ([self.MIMETypeStringOrRegularExpression isKindOfClass:[NSRegularExpression class]]) {
-        NSRegularExpression *regex = (NSRegularExpression *) self.MIMETypeStringOrRegularExpression;
-        NSUInteger numberOfMatches = [regex numberOfMatchesInString:[MIMEType lowercaseString] options:0 range:NSMakeRange(0, [MIMEType length])];
-        return numberOfMatches > 0;
-    } else {
-        @throw [NSException exceptionWithName:NSInvalidArgumentException reason:@"Unable to evaluate match for MIME Type '%@': expected an NSSt" userInfo:nil];
-    }
+    return RKMIMETypeInSet(MIMEType, [NSSet setWithObject:self.MIMETypeStringOrRegularExpression]);
 }
 
 @end
@@ -150,6 +142,11 @@
     }
 }
 
++ (NSSet *)registeredMIMETypes
+{
+    return [NSSet setWithArray:[[self sharedSerialization].registrations valueForKey:@"MIMETypeStringOrRegularExpression"]];
+}
+
 + (id)objectFromData:(NSData *)data MIMEType:(NSString *)MIMEType error:(NSError **)error
 {
     Class<RKSerialization> serializationClass = [self serializationClassForMIMEType:MIMEType];
diff --git a/Code/Support/RKMIMETypes.h b/Code/Support/RKMIMETypes.h
index 79a22886..6119d5da 100644
--- a/Code/Support/RKMIMETypes.h
+++ b/Code/Support/RKMIMETypes.h
@@ -33,3 +33,12 @@ extern NSString * const RKMIMETypeXML;
 
 /// MIME Type text/xml
 extern NSString * const RKMIMETypeTextXML;
+
+/**
+ Returns `YES` if the given MIME Type matches any MIME Type identifiers in the given set.
+ 
+ @param MIMEType The MIME Type to evaluate the match for.
+ @param MIMETypes An `NSSet` object who entries are `NSString` or `NSRegularExpression` objects specifying MIME Types.
+ @return `YES` if the given MIME Type matches any identifier in the set, else `NO`.
+ */
+BOOL RKMIMETypeInSet(NSString *MIMEType, NSSet *MIMETypes);
diff --git a/Code/Support/RKMIMETypes.m b/Code/Support/RKMIMETypes.m
index 7d67a486..f2315992 100644
--- a/Code/Support/RKMIMETypes.m
+++ b/Code/Support/RKMIMETypes.m
@@ -24,3 +24,21 @@ NSString * const RKMIMETypeJSON = @"application/json";
 NSString * const RKMIMETypeFormURLEncoded = @"application/x-www-form-urlencoded";
 NSString * const RKMIMETypeXML = @"application/xml";
 NSString * const RKMIMETypeTextXML = @"text/xml";
+
+BOOL RKMIMETypeInSet(NSString *MIMEType, NSSet *MIMETypes)
+{
+    for (id MIMETypeStringOrRegularExpression in MIMETypes) {
+        if ([MIMETypeStringOrRegularExpression isKindOfClass:[NSString class]]) {
+            return [[MIMEType lowercaseString] isEqualToString:[MIMEType lowercaseString]];
+        } else if ([MIMETypeStringOrRegularExpression isKindOfClass:[NSRegularExpression class]]) {
+            NSRegularExpression *regex = (NSRegularExpression *) MIMETypeStringOrRegularExpression;
+            NSUInteger numberOfMatches = [regex numberOfMatchesInString:[MIMEType lowercaseString] options:0 range:NSMakeRange(0, [MIMEType length])];
+            return numberOfMatches > 0;
+        } else {
+            NSString *reason = [NSString stringWithFormat:@"Unable to evaluate match for MIME Type '%@': expected an `NSString` or `NSRegularExpression`, got a `%@`", MIMEType, NSStringFromClass([MIMEType class])];
+            @throw [NSException exceptionWithName:NSInvalidArgumentException reason:reason userInfo:nil];
+        }
+    }
+    
+    return NO;
+}