I think it's always a little hard to make a judgement about something you haven't experienced first hand. If I had to base my opinion about BF3 on all the (mostly negative) comments I've read on various forums/blogs/twitter accounts - I'd never touch it ... in fact I wouldn't play any game at all.
I don't quite get why it apparently becomes fashion more and more that people dart at "I don't like this, that weapon is crap, the map layout sucks, recoil is too much, ...." paired with "server lag, a noob team, spawnkilling, lazy admins and of course damn cheaters". I can't recall that I saw so much negativity in 2008.
Why do people still play the game? Because some are having fun, those who are able to let themselves into the game and find something they like. If I were to ask - what do you like about BF3 .... I fear the list will be rather short.