An excellent explanation of the confusion that reigns between ASP.Net 2.0 and 3.x

This is something I've come across more than once now - people complaining their ASP.Net 3.5 applications are running as 2.0 and not being able to set them in IIS...

Here's a superb explanation of what 3.0 and 3.5 added to 2.0 - and how they did it without changing the core runtime
http://www.hanselman.com/blog/HowToSetAnIISApplicationOrAppPoolToUseASPNET35RatherThan20.aspx