Here's a great article you might be interested in:
ASP.NET Home: ASP.NET 2.0 (codenamed ASP.NET Whidbey) is the next version of
ASP.NET. See all ASP.NET 2.0 content here.While 100 percent backward
compatible with ASP.NET 1.1, ASP.NET 2.0 brings a number of internal changes
to ASP.NET. These include changes to the code model, compilation, page
lifecycle, and more. This article outlines those changes.
URL:http://msdn.microsoft.com/asp.net/whidbey/default.aspx?pull=/library/en-us/dnvs05/html/Internals.asp#internals_topic9?_r=1