What's nice about it in some ways is that I can create one setting using the disparate locations and stories and you can create another, and they both will be unique. I dunno if the individual pieces model of a campaign world that 4e uses is better or worse than than the large frame that you had to fill in your details that at least 3e followed, but I find that it works for me.
Of course the down side of WotC's policy regarding setting is that if you don't have time to create "your own PoL" from the various peices they've thrown out, you won't see a 4E world that isn't a re-con of a 3E or earlier setting.
That said, you can get a long way towards creating a campaign world by using the published material so far - ie the Dragon articles, DMG information and info pulled from H1, H2 & H3.
Admittedly you won't have an overall campaign map, nor a deep and immersive history, nor will you have everything you'd want if you'd written it yourself. But you will have a lot of great locations that can be planted wherever you want, you'll have a lot of history (although you might need to put it all together in a way that makes sense) and you've got plot hooks galore for your own games.
So, no, there's no official '4e campaign setting'. There is, however, a vast amount of information available that you can build one from.
As Ari said, just because there may never be an official "core" setting from whence came Bael Turath, Arkhosia, Nerath, et cetera, doesn't mean that there will be never be a new setting from Wizards of the Coast. They just don't intend to flesh out the Fourth Edition's "core setting" beyond a few local maps and a bunch of references to past events and fallen polities.Of course the down side of WotC's policy regarding setting is that if you don't have time to create "your own PoL" from the various peices they've thrown out, you won't see a 4E world that isn't a re-con of a 3E or earlier setting. Some GM's and players might not have a problem with that, but others may not enjoy the re-imagining of familiar lands.
Not yet, no. But the folks at WotC have suggested that one of the upcoming "yearly" settings may well be a new creation for 4E, rather than something brought back from prior editions.
That would be great.