For my daily work I do some things in BizTalk 2006 R2. I have Visual Studio 2008 RTM installed on my machine so I was hoping to use that for my BizTalk development. Unfortunatly. I got an email that VS2008 won't support BizTalk until R2 SP1 or the next major version. But don't worry. You can use VS2005 and VS2008 side-by-side (SxS)