I have Visual Studio 2012 RC installed on Windows 8 Release Preview and my question is are there any useful new features not related to Metro, or is Metro what seperates .Net 4 and .Net 4.5?
See What's New in the .NET Framework 4.5 and What's New for Visual C# in Visual Studio 2012.
The biggest new feature of C# 5.0 is better support for asynchronous operations, using the new await keyword.
来源：https://stackoverflow.com/questions/11548373/what-can-i-do-in-c-sharp-5-with-net-4-5-that-i-couldnt-do-in-c-sharp-4-with-n