Common ASP.NET 2.0 conversion issues and solutions
If you are used to 1.1 and plan to move to 2.0, you'd better read this document to learn about the breaking changes and how to fix them!
Even if a conversion wizard will be delivered with the final release of Visual Studio 2005 to better avoid some of the current known issues by automatically implementing the necessary changes, you still have to know about the changes because a conversion/migration is not a final step: you'll have to actually code with ASP.NET 2.0 and so will face the same issues.
One more occasion to warn you: moving to ASP.NET 2.0 will not be a smooth process.