So, I finally downloaded the 15+ gigs, installed it, gave it a go. All I have to say is: holy crap, is this game broken.
The EU servers can't seem to handle the strain, even getting it to log in was a pain because I kept running into a screen that said I have an invalid subscription and have to log into the PSN. Even the forums ware down when I tried to check what was going on. Once I finally managed to access them, they turned out to be pretty useless. Eventually I managed to log in and play. Everything seemed OK during the Braniac ship tutorial instance, but once I got to Gotham it was a mess. Major lag, people asking on chat why they aren't doing any damage, a friend of mine telling me he keeps falling through the floor. I had a little run through the streets of Gotham and, apart from the first area where a few players and some laggy mobs hung out, it was completely empty. Nothing loaded, every once in a while I would take some damage out of thin air, but other than that, the place seemed deserted. I'd understand if this was a beta, but this game has been out for nearly a year now.
Ah well, at least its free, though some people are probably still on subscriptions which would suck right about now. Hopefully they'll fix it soon.