I'm interested in PS4, but I see no reason to buy one yet.
Wii U is doing good but I have not touched mine in a while, mostly because I've been busy and I don't own that many games for it. 3 currently. There are a few I'm interested in, but meh.
I loved the Wii, It has a smallish solid library, like the N64, There are still some games I want for it.
So far the new gen systems are kinda disappointing for me, Nothing really pops out to me, even on the Wii U. I love the game pad, I just wish it was used more.
The 3DS on the other hand (No pun intended) I'm loving, and I only own one game.

There are a lot I want to get and the street pass stuff is cool.
Vita is . . . a thing. It has stuff I think, Sony is doing a terrible job marketing it, even worse than the Wii U, I know nothing about it that would make me want one and never hear about it.