Of course at the same price point PS3 would annihilate the 360. PS3 sells the same worldwide as the 360 every week, which is quite an achievement considering it costs twice as much.
The fact that the US or the UK prefers the 360 doesn't change anything, since worldwide it's a stalemate, it just means there are many other countries that prefer the PS3, like Japan, Germany, France or Spain...
If you want to know why there are so many people who choose to buy PS3 over 360 even if it means paying much more, well that's content, certainly NOT the power of teh cell.
What the PS3 has that the 360 doesn't have ? Games like Team ICO games, uncharted, ratchet, MGS4, LBP, Valkyria Chronicles, Demon's Souls, God of War 3, MAG with 256 players... There's just nothing like that on 360, and when you add games like Killzone 2 or Gran Turismo 5, it's not even close.
On the other hand, to become more attractive, 360 has to make their so called exclusives unavailable on PC. Otherwise people with a PS3/PC combo like me will never feel any urge to buy those games on 360.