I think Orryn is pretty much spot-on, having run 4E myself. I like the game, but I think at this stage in it's life, it is largely a one-tricky pony.
There are just so many things that come across as attempts to "spice things up" or disguise (and I use that word non-judgementally) the simple tactical-combat orientation of 4E. I mean, we've got our terrain, our monsters with fancy abilities, our traps in combat, our skill challenges and so on. Beneath all this lovely stuff, though, is a game that is so dedicated to balance and controlling the experience that it has a strong potential for long-term blandness.
The main solution to the blandness, of course, seems to be "more variety" which WotC wish to provide for you in the form of splatbooks etc. Nothing wrong with that, I just think the OP is right in the comparison he seems to be making, between 1E AD&D at release and 4E.
I imagine that, four years down the road, so much stuff will be out that this problem will be largely forgotten. I do think that it's a potential problem, though, and it's something that makes me slightly unsure about 4E, much as I like it. Oh well, we shall see, I guess.