Does Exchange Service Pack 2 work on SBS2003? YES!
However, if you are working on a client site, please make sure to read Susan’s blog on the subject.
You see, Susan has split us down into two groups. Where as I believe that consultants, or “people like me” are actually both. The key is to have a test bed system (and by that I mean more than just Virtual PC / VMWare).
Oh… for those that have not figured out how to get your 75Gigs… Go to the Exchange Team Blog post here