I plan to buy to a PS3, but not right away. I picked up a Xbox 360 Premium 3 weeks ago. I paid $450 flat CAD. The biggest factor for me getting an Xbox 360 now, and not waiting for the PS3, is the fact the the Xbox 360 can be modded to played back-up games (firmware on DVD-ROM drive can be flashed). I'll save a ton of money. I've already done this. Plus, GOW is out the first week of Nov, and Splinter Cell 4 comes out this week. Two must play games imho. I'm also looking forward to Mass Effect, which looks to be game of the year material.
There is no doubt that most of the PS3 launch games look vastly superior graphically to the Xbox 360 launch games. This was a popular opinion at the recent Tokyo Game Show. It has better hardware, so this shouldn't be a surprise. Graphics aren't everything, and it comes down to games, and game play. Both systems will have great games. Don't be a fanboy,and own both if you can. I would buy a PS3 just to play MGS4, that game alone will sell a ton of PS3's. I hope that a mod for the PS3 will come out within a year of the systems release. Hopefully around this time, Blue Ray DVD Recorders, and blank Blue Ray disc will be affordable (I won't count on it). That'll be around the time I buy a PS3.