As for the PS3, look at the numbers for the sales in the first 3 months. They are actually higher than what the 360's sales were (by 50000 units) and they are also higher than the PS2 and PS1 during the same timeframe. While you can easily say that compared to the Wii it's not doing well, and it's true that the Wii has sold more units, Sony has also produced more units that Nintendo, which is why you can find PS3s and you can't find Wiis. So, don't be so quick to judge the PS3, and like Pck21 said, you gotta give the system some time to catch up with the games. By Christmas this year there should be plenty of great games out that may have a much higher level of graphics than the 360.
I am by no means saying that the PS3 is a better system, I'm just saying that there needs to be a little more time and thought put into the discussion before a winner is decided. Every system has a downside, the PS3 doesn't have a great library yet and is expensive, the 360 is prone to the "red circle of death", the Wii doesn't have very good 3rd party support (Rayman is one of the few games that is good made by Ubi, a 3rd party developer). So, it won't be probably another 2 or 3 years before a clear winner is declarable.
If anyone has the Game Informer magazine from Gamestop, it has a great set of small articles on a whole bunch of these type of articles. (June issue)