Since we know nothing about the next Sony and Microsoft consoles, and not a lot about the WiiU, I think anybody who answers by choosing one of them is a fanboy.

It all depends on the games and the hardware.

Wii U.. cause that's the only one confirmed till now :P

Why exactly would I purchase a Wii U ?
To get ports of PS3 and 360 games ?

Yes. I know that is why I purchased a Wii, to get PS2 and Xbox ports, anyway.

The Wii U since I am a mindless drone (and fanboy) that buys all Nintendo home consoles.

WiiU is the only console i am buying for certain and it comes out first. I may buy PS4 if it gets certain games that WiiU don't. I will never buy XBOX720 because of RROD

Probably a PS4 i've always been late to adopt the other platforms always been more of a playstation fan over anything else

PC until PS4 comes out with its own signature titles (no, not lair or heavenly sword-type signature titles, I mean God of War 4, Uncharted 4, Killzone 4) and possibly the 720 if Halo 5 is anything like Halo 3 (since Halo 4 was announced for the 360). 

An Xbox 720, as all of my friends would get it. Then the ps4 later.