I really can't think of good people for Sony to buy.
Bluepoint and House Marquee don't make sense unless Sony is desperate. Sony would have bought the studios during development like they did with Insomniac, instead of waiting for them to release hits that increase their price. More likely they just have first say on publishing their next games.
Kojima Productions seems to want to be independent.
Everyone else makes too many xbox games.
Let's see if Sony buys Bluepoint right around September.
What else do you know?!