I seriousy wonder why they bought them
They never made an AAA game, their highest scoring game on any Playstation platform is SOCOM II: U.S. Navy SEALs with 87 on Metacritic
Their other SOCOM games on PS2 got 82, 82 and 72. Their SOCOM games on PSP scored 82 and 81. MAG scored 76 on Metacritic.
They don't seem to have any special technical abilities like other first party Sony studios such as Naughty Dog, Guerrilla Games or Polyphony Digital. 256 online game is indeed impressive but it more of an evolution than a revolution since games like Resistance 2 raised the bar before to 60 players online. I'm sure some of Sony's studios could pull off even more players in an online game.
I know we saw very little of SOCOM 4 but seriously.. I doubt it will be anything more than a game in the low 80's on Metacritic
I know you could argue that a lot of the arguments here would apply to Guerrilla Games as well but they proved they can make an AAA game with Killzone 2 which is 91 on Metacritic