It looks like an amazing device hardware-wise, but the software just isn't compelling enough for me at this point. Uncharted seems like the best of the bunch out of the launch lineup, with a few other games like Wipeout, and Army Corps of Hell looking interesting, but not interesting enough to sell me a system.
There are a few things I think Sony could do to make this system really successful.
1) Find the sweet spot between the smartphone/tablet market. I think to do this they need to have a really sweet library of downloadable games in the $5-15 price range. Something that really outshines the phone market, but isn't quite expansive as the console market. Games like Fat Princess, Dungeon Defenders, Shank, Deathspank, Trenched, Shadow Complex, etc would excel on a handheld.
2) Drop the price on the memory cards and software. $100 for 32GB is just too much, especially for an accessory which will pretty much be needed for this device. And some of the software is just way overpriced. I would never pay >$40 for a mobile game regardless quality. $40 should be the absolute maximum, with most titles being priced around $25-$30. Look at games like DH Alliance, and Asphalt. Games which are basically slightly upgraded versions of their iOS counterparts, yet cost 10x as much.
3) Make the Vita version of a game available at a discount for those who already own it on the PS3. The cross play functionality of the Vita is one of the coolest features it has, but there is no way I am paying $60 for a new console game, and then paying an extra $40 for the handheld version. I'm not sure exactly how they could handle this, but I'm sure it could be done.