I'm slowly making my way to the conclusion of Persona 3 FES: The Answer. I was sort of playing it on and off but I'm at the point where most of my personae are strong enough for end game and presumably only a little bit of further grinding is required.
I'm a few hours into Shin Megami Tensei: Nocturne and loving it.
I also recently started Kingdom Hearts 3D. Not a big fan of the Drop Gauge mechanic but I'm still enjoying it.
Virtua Fighter 5 Final Showdown is currently my fighting game of choice but that changes regularly.
QUOTE(Ashtray Heart @ Aug 22 2012, 19:30)

New Super Mario Bros. 2 (3DS)
I expect the secret world you unlock after beating the game to give the real challenge, I haven't started it yet.
Prepare to be disappointed. (IMG:[
invalid]
style_emoticons/default/tongue.gif)
I just recently 100%ed the game (with the exception of accumulating 1,000,000 coins). It was a bit on the easy side but I still really enjoyed it.