IsAnymousType.cs

/// <summary>
/// Attempts to identify an anonymous value using the type name and a variety of common traits
/// (Unlikely this is the best way to determine)
/// </summary>
public static bool IsAnonymousType(object value) {

    //make sure this has a value
    if (value == null) { return false; }

    //check if this is anonymous type using the name and 
    //some values that hint it might be anonymous - This
    //could probably be better though if a better way of
    //checking for anonymous types becomes available
    Type type = value.GetType();
    return Regex.IsMatch(type.FullName, "^(<>f__AnonymousType|VB\\$AnonymousType)") &&
        type.IsSealed &&
        type.IsGenericType &&
        type.BaseType.Equals(typeof(object));

}