Which exclusives would that be? Halo, Gears...
Gran Turismo sells better than Forza.
The rest is pretty even. 360 has 2 highly successful series with multiple releases this generation all of which have sold very well, including the half-game ODST.
I think this perspective, like many had a lot more validity 2 years ago when 360 had a massive WW lead over PS3 in HW sales, now that HW is more even then exclusive sales is closer.
There's also the fact that Japan is still a substantial market for PS3, and Japanese taste in games is very different to the rest of the world, so for all the PS3s in Japan you can basically count them out of selling much in the way of games with a Western vibe (unless they're made by Japanese developers).
360 also has a huge lead over PS3 in Americas and the 2 huge exclusive franchises for 360 enjoy a massive following in North America, Halo especially. It's hardly a surprise that the exclusive more appealing to European sensibilities and not so popular among Americans (Forza) is selling more back in the pack with PS3 exclusives.
Upshot is, the difference is not as much as you might think.
“The fundamental cause of the trouble is that in the modern world the stupid are cocksure while the intelligent are full of doubt.” - Bertrand Russell
"When the power of love overcomes the love of power, the world will know peace."
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