The HTPC Software Thread

[BenchZowner]

Hey guys, I'm in the testing process of a Antec Micro Fusion 350 HTPC Case and I'm now trying to collect some HTPC software to try and since I don't have that much time neither experience in HTPC software I'm calling for you

I'd really appreciate any kind of help such as listing some programs/OSs that you've heard about or tested yourself.

I have a small list ( waiting to grow up ):

LinuxMCE
Windows XP Media Center Edition
Windows Vista Ultimate x86/x64 ( Media Center application )
Nero MediaHome 4
Cyberlink PowerCinema 4 (?) [ maybe it's still on v3, don't remember ]
iMON & iMedia HD
MediaPortal
Creative Entertainment Center
Elisa Media Center
Beyond Media
Entertainer
Freevo
Got All Media
J River Media Center
Meedio Ultimate
Myth TV
SageTV
TVedia
XBMC
Xlobby

Any suggestions ?