Well I was going to say PC, Wii, N64 and MegaDrive (I would say GC > MD but the Wii can play GC games) seeing as that covers all the games I have ever owned so I can objectively say I will enjoy them.

However even without the current gen qualifier you mentioned I was going to say PC, Wii, PS3[phat] and then either X360 or 3DS (probably the latter as there isn't much I would need the X360 for if I have PC and PS3) as they cover the largest library of games between them (Wii plays Wii + GC and has Virtual Console... PS3 plays PS1 & 2 games, and 3DS also covers DS games)

Other combination: PC, PS3, an Android phone or tablet or else. I'll leave the fourth place temporarily free, I like PSV controls and screen, but games are still too few and price still far too high, no way I'll pay more than 150 euros for any portable (or smartphone or tablet, for what matters), less than 130 could increase the probability of my purchase, but just a 100 euros max price could make it almost sure, if there are enough games I like.

1. PC (emulates PS, PS2, Wii, Gamecube and other earlier systems as well as PC games)
2. PSV (backward compatible with PSP and future library)
3. 3DS (backward compatible with DS and future library)
4. PS3 (for HD games that can't be emulated)

Those four systems alone could probably keep me busy for two decades.

PC - Innovative and refreshing PC exclusives as well as emulation.
PS3 - Where most of my favourite games are.
Wii - Refreshing motion control games and backwards compatibility with the Gamecube.
PSV - A powerful portable tool that can play my favourite PS1 and PSP games and will hopefully recieve more games in the future.

Not much of a challenge as there are many gamers that don't have four gaming devices as we speak. They aren't sacrificing much.

As it stands, I own everything. Wii, PS3, Vita, 3DS, 360, DS, PSP, etc. I'd go with:

3DS: Because I'm fucking in love with the device right now. Gives me access to my DS library, too.
Vita: Because most of my PSP games work on it and I love the PSP.
360: My current favorite and most played console
Wii: Because it offers a different style of game than the 360.

Why no PS3? I had to sacrifice one of the HD Twins to get the most variety.
Why no PC? Fuck the PC.
Why no PSP or DS? You can play their games on the older console.
I'm also gonna dump the Wii the night before the Wii U arrives.

I wanted to add tablet and smartphone, but there aren't enough response options in the poll function to give enough variations for 3 or 4 of 8 options. As it is there are lots of options of the 6 I do list that are not response options.

With phones / tablets in the mix I think I'd go for the Galaxy SIII over a 3DS. Almost a big enough screen to be a tablet and it's a phone. Or maybe a Galaxy Note, which IS a tablet and phone; though too big to fit in a pocket so I'd have to get a man bag. I pretty much only play Sudoku on my phone at the moment so my on the go gaming needs are pretty simple. I did just get Where's My Water but haven't started playing it yet.

PC
Wii
3DS
.....
i would never buy a Msoft console no matter how good it is (not saying that the Xbox is very good)
and the PS3 was a disappoinment compared to its great predecessors, so....

im buying WiiU day one

I'd get myself a godly PC, a Wii, and a 3DS. Then I guess I'd get a Vita, cause it needs the help.

3DS XL
Vita
Ipad
PC

PC, PS3, PSV and 3DS for me.