I tried the wireless media server thing for the first time tonight with my PS3 and XP computer. I couldn't seem to get my fancy Kaspersky Internet Suite to allow network traffice properly but I turned its firewall off and turned on the windows firewall. The PS3 showed up right away, although it was listed as an "unknown device".
I also had to upgrade to Windows Media Player 11 since I believe this is the only one to allow media sharing.
The PS3 saw the shared files with no problems. We watched a couple of DivX TV shows (missed espisodes from flaky PVR...) and it worked quite well.
One show I copied to the PS3 hard drive and of course it worked perfectly. The other we tried streaming and it cut out a couple of times. It reconnected immediately and I could restart from about where we left off. However, this is likely a signal strength problem since I can't get my signal strength above 45% and it often dips in the the 30's. I'm not sure why since it is only about 25 feet away through one wall and some furniture.
Anyway, I'll likely copy most things to the HD in my case but if your signal strength is good, music and video streaming shoud be fine.
Up - 51H83/HTR-5550/Point 5/RP-62/6208-HD
Down - 50PHD8UK/HTR-5840S/Micra 6/DVD-S77/6412-PVR
My DVD Collection