The question is too vague. Do you mean software sales? Quality? Quantity? A mix of the three?
I'll just answer the sales by saying yes I think Sony will start selling more software once it passes the 360 worldwide.
As far as quality and quantity of software, I don't think it'll ever happen. The 360 will always have the advantage of easy porting with PC games, and that trend is still continuing with Left 4 Dead and Command and Conquer Red Alert 3 not seeing the light of day on PS3. There are also games like APB, Champions Online, Age of Conan, Huxley, Supreme Commander, Splinter Cell Conviction, Universe At War, Velvet Assassin, Warhammer: Battle March, Dungeon Hero and Venetica, among others. This was also a trend from the original Xbox in comparison to the PS2.
All of the console third parties are almost entirely going multiplat so that's basically a wash.
Micosoft has bought so much Japanese support that Sony can't even match it even with multiple times more consoles sold in Japan. This could change in the future if Sony gets a real foothold in the market and can sell software in Japan, but for now Microsoft's money is talking to Namco, Square-Enix and Atlus. Even so, they'll always have Mistwalker support, who have delivered two RPGs already and are better at getting their games out than Square's been.
The only thing Sony has in it's arsenal it's it's superior first party against Microsoft's which could prove to be Microsoft's undoing if they don't improve their own. I do see Microsoft making strides in good first party support though. Halo Wars, Viva Pinata 2, Banjo-Kazooie 3, Forza 3(if rumors are true), Halo Chronicles, Fable 2, Kingdom Under Fire 2, etc. They have a long way to go to match Sony's first party though.
