Ill wait a few weeks until destination playstation and see if the announce a new system for this year or next year if so grab a wii u. Pretty sure vita will have similar features as it does with ps3 with their new system.
Wii U... Launch console, still has bugs to work out, small library (good for a launch console, but still small). Backwards compatible with Wii (though not GameCube), including Wii's Virtual Console and WiiWare, plus its own eShop. Small onboard memory storage, expandable via external hard drive. Only place to play 1st party Nintendo games, if different enough from the competition, likely to get many 3rd party exclusives.
PS3... Last gen console, well developed library, inexpensive, thoroughly debugged. Backwards compatible with PS1 games, a variety of games available on PSN including but not limited to PS1 and PS2 games. Substantial onboard memory storage, various console models with different internal hard drive sizes. Only place for 1st party Sony games, significant library overlap with Xbox 360.
They're both worth it one way or another. Wii U would probably be the better value if you never had a Wii, since you get two game libraries with one purchase, and new games will be coming out for it for a good half a decade, though since it's current library is small, you'd probably spend most of your time with Wii games. Then again, if you never owned a PS3 or 360, a number of high profile current gen games were ported to the Wii U.
If you did or do own a Wii however, PS3 is by far the better choice. By not quite as far though if you own or owned a 360.
Surrender and I will destroy you peacefully. R.E.G.I.S. mk5 - Megas XLR