It depends on how you look at it. You're talking about the graphics processors. I have seen articles talking about the difference, and it may be true that the PS3 cannot push the same amount of pure graphical power that the 360 can. However, it does have more processing power that can be used to make up for some of what it lacks with the RSX, and perhaps more importantly, to make games much more immersive, realistic and ultimately, more fun, because it can handle many different functions related to how the game works (not just how it looks) at the same time. I realize this is mostly just theory at this point, but it is theoretically true, and since the statement was that it "will be" the best all around system out there, I don't think you can dismiss it that easily. There are also many standard on-board features that the PS3 has over the 360 (BD, WiFi, etc). Comparing the two strictly based on graphical prowess is a little shortsighted, IMO.
You also never said whether you own or have even played with a PS3, and since your comparison was PS3 vs. PS2 (you never mentioned 360 until now), I'm still curious to know what that answer is.