The four big ones are Mirror's Edge, Singularity, Darksiders and Persona 3 FES.  

Mirror's Edge and Singularity I've beaten. Mirror's Edge was fun. I managed to get through it without a hitch, and without feeling like I was wasting my time. Aside from the combat, of course. I had to retry levels a bunch, and I died a lot, but it was a fun experience overall.  
 
Singularity was interesting. A nice little reprieve after Mirror's Edge. It's fun, it's got an interesting game mechanic, and the story fits together as long as you don't think about it too much. Basically, everything I think about the game Jeff already mentioned in his review. One thing I wanted to touch on, though, was the weapon upgrade system. In a game that's only about six hours long, it doesn't really make much sense to include so many things to upgrade. It made sense when Bioshock was about 12+ hours long, but in a game like Singularity, it baffled me, and distracted me from the game quite a bit. I ended up getting barely half of the upgrades, and depending on your play style, you might get even less, because I was going crazy all over the place looking for E99 tech. Half the weapons in the game are there for some variety and aren't actually very useful. I just stuck with the assault rifle and shotgun. Bottom line - if you're interested in it, get it, because all the stuff I mentioned is kinda trivial anyway. 
 
Third, Darksiders. I beat the second dungeon (A bit of a disappointing boss, I thought) and got... a gun? Yeah. I'm enjoying Darksiders, though. Going through dungeons and beating bosses for new weapons and solving puzzles in a Zelda-like fashion will tide me over until... well, the next Zelda. 
 
Finally, Persona 3 FES. Now, I put this game on hold for a few months (Read: a year) after being seriously under-leveled, and started up again with the recent release of Persona 3 Portable. I think I'm on floor 100-ish of Tartarus. I figure I can beat Persona 3, then play through it again on my PSP as the female protagonist for some new content. The ability to control your other team members Persona 4 style is a nice addition, too. I still wish I could just take my save from my PS2 and throw it into my PSP, though. Oh well. More content, right?  
 
I'm also brushing up on my Team Fortress 2 skills for the awesome TNT this week.
 
So that's what I've been playing, mainly. I also dumped a massive edit on the Osu! page a while ago if anyone wants to check it out and make some changes. 
 
What have you been playing?