I have 3 out of 25 with Win7 Pro, the remaining still on XP/SP3. Simple things like off-line replication don't work, or accessing files from network slow and faulty, can't send faxes via the sbs2003 fax server.
It's all Microsoft, no third party software, it should all work.
I'm not throwing out an entire domain of hardware and software after spending thousands building it, just to accomodate windows 7. it ain't all that wunderbar, or not any better than xp when it comes down to basic business purpose.
If MS wants to upgrade my server software for free, and all related equipment that becomes obsolete or disfunctional with the 'new' packaged software, maybe it will work, but that's not why i'm here.