I work* for Wizards and I can assure that 4E is already in the works. The release date wasn't made clear to me.
The market research has been pretty clear that the release of a new edition has a limited shelf life because of the aging of the hobbiests and replacement by computer/console gaming. They are of the pre-emptive thinking that 4E NEEDS to be released while there is someone who will still purchase a paper and pencil game. To sweeten the deal, miniatures and collectable rulesets will play a larger role in encouraging the purchase of more product. Why put out the COmplete Arcane when you can put out the Complete Arcane Miniatures with 4 different core class rulesets.
Now these are just rumors, but the following is what the playtesters have been dealing with:
* Prestige classes will be replaced by collectable core class options (full packages with feat lists exclusive to those classes)
* Miniature variations including mounted versions and other things players have been asking for. They're going to be encouraging people to take prepainted mini's and 'make them better.' Someone said that it might mean that they could be doing interchangable "attachments" kind of like the old GIJoe's.
* d20 licenses will remain, but the requirements will include miniature releases, which should tighten the market sales because 'hobbiests' won't be able to release miniatures. PDF downloads from 3rd parties would also be eliminated.
* The magic and combat systems have already been previewed in books like 9-Swords, etc. Ramping up of power throughout an encounter will be the rule rather than "once per day" type abilities or the so-called "vancian" spell slot magic system. They're NOT looking to spell points (or character points).
* Skills and feats will remain, but will be better and more clearly tree'd (and reduced in number).
* Magical itmes is the big one. Playtesters have noted that they're presented in a "collectable format." The DMG will have the main ones, which will actually be printable handouts (like the old LC certs), but new ones will be in their "Collectable" format..whatever that means. I kind of like the idea of those 'certs.' I can only imagine what it will do to Dragon magazine! If you have one page or a half-page per certed item. Would they have variants on the same page (for example +1-+5 generic sword wouldn't need 5 sheets..just one with a check-mark). Considering the talk about the 'variable' miniature accessories, I can imagine this will be a hot thing.
* It sounds more like toys and cards to me, but cool nonetheless. I sure it's just to sell more product.
* Thought: wth all these modifiable accessories to the miniatures, i wouldn't be surprised if they had to change the scale and make them larger.
jh
* Actually I'm as a product-promoter, i.e. a DM for a home group..so in a sense I work for Wizards when I require my players to purchase their own PHB
