I'm a Nintendo gamer. Waiting two years after a game is announced is the norm. Even if the announcement trailer makes the game seem close to done.

I've been saying this forever.

And what's interesting about the Nintendo games is that all of them I can remember end up looking just as good graphically, if not better than they did at the reveal/announcement; the gameplay is never broken; the core design is always solid (whether or not it works and is fun is another story; see Yoshi's New Island or Wii Music); and you have a reasonable idea of what to expect.

We see with Watch_Dogs, Aliens: Colonial Marines, etc. that games can be graphically downgraded to the point of resembling something else entirely; gameplay is broken, buggy, or terrible; there's a ridiculous amount of hype around nothing of substance; and they continuously get delayed for no reason. (supposedly, to improve the game, but Watch Dogs clearly just decided to downgrade graphics and has terrible physics bugs)

That is true, Nintendo games have a very high level of polish.  Sometimes though I would be willing to trade at least some amount of that polish for a higher volume of games.  With big budget console titles it makes more sense to take a long time, but when they show off a handheld game that basically looks done and then it's multiple years until it's released it's a little confusing.

For better or for worse, Sony started the whole culture of announcing games 2 years in advance so now everybody seems to do it. It is great for short term excitement and really great for people who love list wars lol

I'm pretty confident that among the recent to 2015 delays, several will be delayed until 2016

Yeah, I agree, they are anouncing games too early these days...

Yes and no.
I don't see the problem with an early trailer, just let the people know where the game is in development. It's the dates and timeframes that are beeing set too early.

sorry, but with all leaks we see before game announced, can devs really push more the info at later time ?

yes, without a doubt.