I' with Ranger REG here, at least about the desired release date: not in this decade. Especially because I think that D&D is nice as it is now. I have only two or three things that I would want to see changed, and they aren't enough for a new ruleset, not by a long way. (These are sorcerers as their own class, druids and rangers with spontaneous casting, and something to lower the dependency on magic items)
So when there is to be D&D 4e, it should take it's time - till 2010 - and then do some nice changes all around, but, if this is possible, be largely compatible to 3e (which should not be too difficult, if they keep the classes, the races, and the system of skills and feats, the d20 mechanic, and how ability scores work).