Five years later...

And there are still a lot of applications in need of migration from 2003 to 2005. I understand you had to build it first, then deploy and operate it, but for those of you ready to move, I get a lot of questions regarding "how hard" and "how much work" and so forth. Unfortunately each project is unique, so start here: Daniel Moth wrote up an excellent summary with links to lists of breaking changes, etc.