It's pretty that at the moment, Sony doesn't care if the PS3 beats the 360 or not. The only thing the big boys at Sony want is that SCE starts making some money instead of losing a shitload of it.
Promotring first-party games is a part of SCE's strategy to make money (so is keeping the PS2 alive as long as possible), SCE can make a lot of money buy selling FP games (look at Nintendo).
Now, eventually, SCE will actually make profits (hopefully for them, this fiscal year will be profitable). When they have profit, they have a lot of extra money to spend, money they can spend at buying some exclusives. But will they do so?
I believe they should, MS will keep doing it to hurt the PS3. For example, securing Versus XIII's exclusivity will help the sales (we all know FF XIII has a much bigger effect sales wise though), so will other games. They can be JRPG's, they can be other, western games.
What do you think of this? Will Sony start buying some exclusives eventually, or will they keep their 'we don't moneyhat' attitude, even after they have the money?
