When your 90 days trail period expired for VS 2008, it gives you an option to upgrade it and goes to MSDN page. On that page, its about Visual Studio and has nothing to do with Upgrade.
I would think Microsoft should put an automatic upgrade by just providing the product key.
Annoying ... annoying .. annoying ..
Anybody had same problem? How did you solve it? One way to do is, Uninstall evaluation version and reinstall it.