I think that's why they call it split-screen co-op and not online co-op.
I'll be getting it for the music-generation-based game mode in the add-on.
The PAIN post
on the PS Blog confuses the
out of me because it makes it seem like the trophies are stuck to the new level DLC, either that you'll need to buy it to get the trophy update or that it's not coming out until then.
Either way, the Bionic Commando Rearmed post
on the PS Blog suggests that trophies will probably be coming to the game sometime after the game's launched.