Yes, I have played it. I've played, and own, all of the games that I mentioned.
Clearly our opinions on BS2 differ, and that's ok. I'm glad that you liked it more than me. I wasn't cynical about its release; I was really looking forward to it and hoping it would be more than I felt I got.
I personally felt that the solo game while technically as nice as the first didn't really bring anything that excited me terrifically. Some of the scenery was nice with more deep-sea pretty stuff going on, but otherwise it felt like the main character was just a re-skinned version of the first game.
It did have some pretty cool points - and it's not a bad game at all, don't get me wrong - but it just didn't bring the excitement that the first one did. Rapture just didn't have the same punch in round 2 for me, I guess.
I almost wish I'd bought the collector's edition just for the cool stuff that came with it. If I could've bought a pack in-store of just the posters and whatnot *without* the game I probably would've, even. (I'm sure I could ebay for it or something if I really felt like it, but I'm not going to.)
And the multiplayer, as I said, felt cheap to me like a blatant fan-service that didn't provide any depth to the experience, just... well, deathmatch, which I can play in a billion other games and have exactly the same experience - only better, because there are other games really built around that style of play rather than shoving that style of play into a world that in my opinion gained little to nothing from it.
But by all means don't let my opinions keep you from playing it - it's a game, and if you enjoy it keep rocking it. That's what it's there for!