Polls look similar right now except more people on VGC will probably answer bought on other system more (and more people saying it isn't my type of game on NintendoLife).

Nope, wouldn't touch it if it came to Wii U. Already have a 360 but I'm not touching it on that either.
I have no interest in the gamer whatsoever, prior GTA titles did not impress me and I haven't seen anything to suggest this one will be any different.

GTA V from what I've played so far (on 360) is an excellent game (a good leap over older games in the series), also it would be a perfect fit for the WiiU controller imo.
If the game had a good controller implementation I would likely buy for WiiU, if not I would choose PC version for better graphics and resolution.

YES LOOK AT THE POTENTIAL:

No, simply because I already bought it on 360. If it came to PS4 or Xbox One I would consider picking up a copy for one of them probably Xbox One.

Do you even have a Nintendo platform to begin with.

I own 3DS, I've never owned a Nintendo console. All though I plan on buying the Wii U and it being the first CONSOLE from Nintendo I buy. 

Nah, not my thing in the slightest, at all.

I don't have a Wii U and don't plan to get one, but I really like it if games release on as many platforms as possible, so that a lot of people can enjoy them.

But: Does Nintendo even allow mandatory installs (especially if they are ~8GB big)? While the WiiU-"BD"-drive is a lot faster compared to the optical drives in the PS360, I think that seek-times are still way to high compared to an install on HDD/flash.

Yeah, probably. I'm loving it now, so why not?