PS2 sold ~160m, so no...

Yeah it's going to keep it afloat for somewhat longer, a handheld that is already dropping off very fast

If you reduce smartphone and tablet gaming to Angry Birds and Candy Crush, you will never understand why these mobile platforms get more and more popular for gaming.

The diversity is enormous, you can find some good games of every genre in the AppStores: point&click adventures, visual novels, racing games, strategy games, puzzle games, jump&runs, action games, rhythm games, RPGs, board games, card games, tower defense games, ... even stealth games like the great "République".

Of course some genres work much better with touch screen controls or motion sensors than others, but even in the problematic genres like jump&runs, there are a few games which work exceptionally well for their input restrictions... Rayman Jungle/Fiesta Run & Leo's Fortune for example.

PS4 - wii U the gap will be bigger than the total sales of the 3DS

Your PS4 number is way too low while your WiiU number is way too high. WiiU is behind GC in the same timeframe while GC only had a total of about 21 million units. The PS3 will probably reach 90 million units, so it's clear that the PS4 will have a much higher total. The handheld numbers are about right I guess.

Hard to say imho. It will mostly depend on the sales performance of the PS4.

My current guesses for the end of gen sales are:
WiiU: 20m
Vita: 18m
3DS: 95m
PS4: 120m

But I'm really unsure about the PS4. I think that it's possible that because of cloud gaming there will be no real successor to the PS4 and thus the PS4 might be on sale for a very long time. On the other hand just the opposite might happen. The current gen systems are somewhat underpowered and it might be neccessary to make this gen a shorter one with a release of all next-gen systems by 2018 (especially if VR-gaming is a success it might be reasonable to release the next-gen early on); this in turn would of course hurt the sales of current gen systems. So anything between 75m and 150m for the PS4 is possible. And how would we treat a streaming-only "PS4"?

I don't think this is even a question. We know that the Vita won't do very well at all and likely quite a bit less than the Wii U and the 3DS should manage to beat it probably at least 4.5 times in lifetime sales. The big one, however, is that the PS4 seems set for 90 million as the bare minimum and probably in the 100 million region and the Wii U appears destined since the beginning for the 18-20 million region, making this an obvious answer; the Wii U-PS4 gap will be the largest by far, and I think by as much as 20-25 million.

LT guesses (pretty much in line with numbers since 2012/2013) for me:

Vita: 15-18 million, very likely much closer to the 15 million end of the spectrum.

3DS: 70-75 million, a bit down from my 2012/2013 assessment, it's down significantly is sellthrough yoy and heavily in shipments.

Wii U: 18-22 million, lowering the 25 million cap to about 22 million seems to make sense, even it managed another semi-decent year (as in; same as 2014) it would still only reach the very hems of the Gamecube's skirt at this point.

PS4: 90-105 million, no doubt I have been underestimating this machine for 2014 but I still believe it will have a rather early peak and a significantly shorter lifespan than the PS3, with the numbers being what they are though; it should comfortably outsell it in lifetime figures.