From memory there was a thread around here somewhere with people that were running it. I am looking at doing this also I think it depends on the purpose you are doing it.
If you are wanting to use the WHS as a server for gbpvr then, once again from memory, it works fine. If you are wanting to use WHS as a server and as your main media centre then it was much more trouble, i think it was to do with the graphic capabilities of the WHS software.
I ran WHS with GBPVR for a while. It worked for a few weeks and then the server stopped recording. I'm guessing that files got corrupted. I have found that with WHS if you try to get it to do things outside what it is supposed to do then you run into problems (anything other than serving and backing up).
Bigbus
[SIZE="1"]NPVR Server: AMD Athlon Dual Core 5200, 3 GB RAM, 128GB SSHD, WinTV HVR-1600 QAM (2), Hauppauge WinTV-DCR-2650, Win7 Windows Home Server 2011: Athlon Dual Core 4600+, 2.5GB RAM, 5 TB HD Clients: AMD64 Laptop, AMD Athlon 4600+, AMD Athlon 3200+, Toshiba NB205 Netbook, Raspberry Pi (Raspbmc), several other laptops, android phones, and iPods [/SIZE]