What can I do in C# 5 with .Net 4.5 that I couldn't do in C# 4 with .Net 4?
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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?

If so I would love to see some real world examples of the new features.

Thanks