For the record, 3 Floyds is still kicking ass.
Yes, as their production increased they started distributing more of some of their staples, namely Gumballhead, and yes, even Zombie Dust, to a wider market. Cripes, I've been able to walk in to FFFs on a Tuesday evening twice in the last month and there was tons of Zombie Dust, and no line. So, its basically that when you can't get something, you want it more. And now that you can get it easily, why rush to buy? The other side of the coin is that there is, as PhinMatt says, a lot of other really good stuff being brewed all over, and so there's more real competition.
I guess I have a different perspective on Floyds, because I can go there regularly, and get to drink the stuff that they only sell in the pub, and that doesn't reach distribution. Case in point was Quaanto, a Triple IPA - basically Permanent Funeral on steroids. Ridiculously good. There's always great things on at the bar or on sale to go in the kiosk that you'll never see in Indy, unfortunately.
And my last comment is that Gumballhead should revert back to being a seasonal beer. When it first came out, it was only available from like April to September, and then poof! it was gone. It is a tremendous summer beer, but for some reason I just don't care for it in the winter.