Marvel Chronology Project

Note that some of the flashbacks are inconsistent with 616 continuity- for example, Scott, Warren, Bobby and Hank are depicted as meeting Jean during the fight with the Conquistador.

Also, Manhattan was an uninhabited wasteland for over a decade (!) following the Human Torch/Sub-Mariner fight.

I was going to ask somewhere if Grand Design was canon (or intended to be new, post-Secret Wars canon). I haven't read it yet, but this review suggests it can't be canon, because it (by design) doesn't care about anything published after 1991 or so, and therefore is removing setup for stories after then:
http://www.housetoastonish.com/?p=4000

The problem isn't that it doesn't mention anything after 1991- that in and of itself isn't enough to strike a series from canon- but that it's a resequencing of events- for example, Xavier doesn't meet Moira until after he loses the use of his legs.

Plus the Watcher is currently dead..

The story reads like a fanboy's idea of how the X-Men back story possibly should have been told, given fifty years of hindsight. There are some good ideas in it, and possibly some of them could fit with 616 continuity, but to make most of them fit, Piskor has had to reshuffle and alter a number of story elements, and that's simply not how it happened.

Yeah. It's really entertaining and VERY cleverly done, but I don't think it's even meant to be canon--it's just an exercise in nudging all the pieces into what would have been a more elegant form.

(Which is a pity, because some of its ideas could still be implemented if someone wanted to: as Paul O'Brien points out, the Phoenix force coming after Jean from the moment her powers first manifested, and all the alien cultures immediately taking note of that, makes a whole lot of formless plotting snap into shape.)