I forgot to mention one of the most obvious changes in ASP.NET 2.0 beta 2: the fact that the “special” directory names changed. The Code directory is now named App_Code, Resources is named App_GlobalResources, LocalResources is named App_LocalResources, and so on.
Speaking of resources, the Page methods named GetAppResourceObject and GetPageResourceObject, which can be used to load resources, were renamed GetGlobalResourceObject and GetLocalResourceObject, respectively.
Also, I discovered that on one of my machines, the ASP.NET tab was missing from the IIS management console after I upgraded to beta 2. Turns out this is due to a bug in the beta 1 uninstall, and you can fix it by removing all version keys except 2.0.0.0 from the following registry keys:
HKEY_CLASSES_ROOTCLSID{7D23CCC6-A390-406E-AB67-2F8B7558F6F6}InprocServer32
HKEY_CLASSES_ROOTCLSID{FD5CD8B1-6FE0-44F3-BBFB-65E3655B096E} InprocServer32
HKEY_CLASSES_ROOTCLSID{FEDB2179-2335-48F0-AA28-5CDA35A2B36D}InprocServer32
Or, in my case, I simply deleted these registry keys and ran aspnet_regiis -i.
You may have noticed that Precompile.axd and Webadmin.axd went missing, too. You now precompile a site by using aspnet_compiler from the command line or Visual Studio’s Build->Publish command. As for Webadmin.axd, forget about it. The Web Site Administration Tool can now only be accessed from Visual Studio. The ASP.NET team decided that it was too risky to expose the WSAT on production servers, especially shared hosting servers.