Continues to get HD JRPG remakes, which is a plus to me. If you want value in games and like the genre, they give you tons of gameplay. With PS+, you get at least a handful of the must-have games for Vita. I wouldn't say there's an abundance of original games, but I really want to get around to Soul Sacrifice and see if that's any good.
I think there are two main groups of games that you'll get a lot of: (1) the typical Sony stuff like Killzone, God of War, Super Stardust, Wipeout , and then (2) strange Japanese stuff.. mostly downloadable and relatively cheap. If you are interested in Persona 4, that and one or two other things make it a buy, IMHO.
I think the biggest thing you have to consider is: do you want any portable machine? For me, I don't use it much as a portable machine, but more often just to have on the couch while I ignore watching a TV show, or while watching Giantbomb livestreams. I don't have a bus commute every day like some people, but it's still fun to play at home, too.