Want to shift from ASP.NET 2.0 to ASP.NET 3.5

Hi,

I have been working mostly on ASP.NET 2.0. Now i want to shift to ASP.NET 3.5.

I would like to know if  i start with ASP.NET 3.5, what the things i need to know.

Right now the most important thing for me is with the existing websites which was built in ASP.NET 2.0. If i work in Visual Studio 2008 with 3.5 framework Will these websites work or i need to modify.

Please also suggest me what are the things specially i need to know about ASP.NET 3.5

Thanks.

Regards

Arshad
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