Merric has a nice overview of what we've seen of D&D's 4th edition so far, and his thoughts on same:
There's one thing that has been very nice throughout the 3e era: I've felt like I was Wizards' target audience. Not always, but for most of it. Of course, they occasionally got my tastes dead wrong - there'd be a lot more adventures from Wizards if they were aiming directly at me, and a lot of Greyhawk ones at that! - but ruleswise? Nice going.
The biggest thing about 4e for me is the potential it has to fix the problems I've had with 3e. The biggest disappointment? The way its publicity has been handled.
If there's one thing that really makes me cringe, it's that "teaser" video displaying the "problems" with the previous editions of D&D. Now, I - and most people familiar with 3e - can relate to the problems with Grappling in 3e. (Incidentally, I don't have a problem running Grappling, I just have a problem with how powerful it is with large creatures). However, the problem with AD&D is... you don't know what mini stands for which monster? Huh? How on earth is that a 1st edition problem?
4e got off to a bad start, and things haven't gone smoothly since then.
Myself, I feel oddly disconnected. When 2nd and 3rd editions were rolling out, I was deeply, passionately involved in what was happening, and following every scrap of information with the intensity of a starving wolf tracking a lame caribou. But I've lived without the latest version of D&D for a while now. 4th edition looks interesting, but not nearly as much fun as
True20 is right now. My dreams of being a professional pen-and-paper game designer have deflated under the reality of hobbiest wages. I'm just having fun, now. With the net and online play, there's no reason to feel saddled to what the corporations are doing.
On the one hand, I feel liberated. On the other, I recognize that attitudes such as mine are the death-knell of an industry. What will happen when all our games are put out by Forgites and Wayne Reynolds is forced to illustrate get-well and birthday cards to keep a roof over his head? Yeah, there will still be free or cheap content, but you really do get what you pay for.
But all of that isn't really related to Merric's post, just thoughts inspired by it. Merric gives a nice overview of the basic themes we've been able to see about 4th edition so far. If you haven't been keeping up with it, he's written a good primer as to where things stand now.