Don't. Have both.

The PS4 does of course have obvious advantages like a better online infrastructure, better graphics and multi-plat performance, more multi-media functionality, bigger HDD and so forth, but at the end of the day the biggest difference between the two is games. Look at Nintendo's 1st party vs Sony's 1st party + 3rd party support (if you don't have a decent PC to play them, or PS3/360 in the short term) and choose whichever you think will best fit your personal game preferences.

Or just get both

You instantly become a better person when owning a PS4, much higher social standing and for that to fully work you also need to get of the Wii U, after all owning that really tarnishes peoples reputation.

Oh and Infamous is pretty cool.

There are 30 games out for the WiiU?

No it's not, Gamestop currently gives you 156 for a Wii U.

They both have great games that the other doesn't right now and in the future. I would keep it AND buy a PS4 eventually when you have the money. Also maybe sell some of those 30 games that aren't up to snuff and just keep your very favorites like I do :)

it has watch dogs

If you do that than you are the .... of the year ;)

Ditch the Vita then. You can play your PS4 and share screenshots and videos! That's a pretty neat thing to do.