It's too soon to tell.
I like what we've seen of the system, but I'm really not interested in another 1,000 page monstrosity of a ruleset (or, worse, one that somehow feels incomplete without another 1,000 pages of supplements). Based on what we've seen, I don't think there's any need for that, but whether WotC would be able to help themselves is another question.
(And, of course, it's extremely doubtful whether they can make money on a 250-page game that doesn't feel like it needs supplements.)
So as things stands, I like what I see, I'm actually quite surprised at how much I like what I see... and I still probably won't buy it.