Although you can still develop for .NET 2.0:
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Scott Guthrie, a general manager in the Microsoft Developer Division, said in a blog post on Nov. 19: "VS 2008 enables you to build applications that target multiple versions of the .Net Framework. This means you can use VS 2008 to open, edit and build existing .NET 2.0 and ASP.NET 2.0 applications (including ASP.NET 2.0 applications using ASP.NET AJAX 1.0), and continue to deploy these application on .NET 2.0 machines.
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