-Updated main project to .NET 4.0
-Updated to psake 4.0
-Changed assembly version to 4.0.0.0
-Added ICustomTypeDescriptor implementation to JObject, removed JTypeDescriptionProvider and JTypeDescriptor
-Changed serialization of collections to use iterator rather than indexer
-Removed Compact Framework project
-Fixed XML documentation warnings
-Fixed decimals to always be written with a decimal place
-Replaced IMappingResolver with IContractResolver
-Renamed JsonMemberMapping to JsonProperty
-Added JsonContract, JsonObjectContract, JsonArrayContract, JsonDictionaryContract
-Added support for OnSerializing, OnSerialized, OnDeserializing, OnDeserialized callback methods
-Major refactoring of serialization internals
New feature - LINQ to JSON!
New feature - Ability to specify how JsonSerializer handles null values when serializing/deserializing.
New feature - Ability to specify how JsonSerializer handles missing values when deserializing.
Change - Improved support for reading and writing JavaScript constructors.
Change - A new JsonWriter can now write additional tokens without erroring.
Bug fix - JsonSerializer handles deserializing dictionaries where the key isn't a string.
Bug fix - JsonReader now correctly parses hex character codes.