Diagree, with 8GB GDDR5 and using the GPU to offset performance later in life, it can easily last a good 6-7 years, now that doesnt mean it wont be replaced within that time, in fact i think a shorter timeframe (5 years max), but PS4 will do just fine and will imho do better than PS3.

Also consoles dont give a shit how outdated they are against PCs, the length of the last gen proved that. But if Sony do massively dominate, then the other 2 players will restart the next cycle earlier. So we could be looking at a 4-5 year cycle if the competition is left with no other choice but to move on. 

Wii 2008 was explosive, no way PS4 stands a chance. Wii post 2009 becomes a better competition. Think it definitely has a chance to beat the Wii after that, but too early to call. Lots more twists to come

Yeah no doubt, Nintendo's Wii-u will be replaced within 2-3 years now (though that would make it 5 years or so on the market) but they will want to get out before the current gen consoles... I can really see MS bringing about a change within 5 years, and even 4 years, but it would have to be a console that builds on the current one otherwise they will get problems with early gen games (or lack of) like this gen. That's why I think Sony have got it sorted, theirs is a very uncomplicated product, they can easily improve it in 4 years time.. while this 32 ESRAM thing that MS have, that could be more problematic... but then 4 years tech wise is a long time.

As I said before...With these consoles being PC architecture I think the PS5 and X(2!) will be just upgraded versions (really all they will need to be) They will get a more powerful APU (Cpu/Gpu combos) and more memory. Probably be 16GB or more.. using (G)DDR6 maybe.. This will be a much easier transition. All games will be backwards compatible with previous gen.. updated OS etc. If VR does take off the systems will be BETTER equipped to handle that. All of this will more like if you just bought a new computer 5 years later.. up to date tech etc... but user experience not much different.

Microsoft and Nintendo may be the one to shorten this generation. Microsoft is the one who could do this first with adding more memory etc. Even games from the new generation could work like PC and still play on X1 just ast a low setting.. where the newer games on X2 would be like ultra settings.

Its a lot of throughput power, I don't disagree. But you can already see that developers overshoot on inefficient graphical fidelity and end up having to revert due to hardware limitations even on this new super-duper hardware. The problem that compounds on it is that x86 architecture just isn't as efficient as PPC GPGPU at the whole gaming thing. x86 allows for a lot more multitasking and social things and aspects (as well as codecs).

Multimedia device or console?

Only if it follows the PS360 sales curve, when the fourth and fifth years sales where higher than the "3rd year peak" and than drop slow the 6th and 7th...

I don´t think it´s safe to predict how the market will behave the next decade.

I doubt it but let's wait for E3...

Naturally it's never safe to predict something like, but it is still at this point a very real possibility.

The important part for the Wii is 2009 onwards, From that point on, it had an almost exponential decline in sales, something I doubt the PS4 will have. This will be when the PS4 would certainly overtake it.