It is also possible that NVidia is using misdirection in their statements to confuse the competition. As Sun Tzu said, "When the trees move, the enemy is coming; when there are many blinds in the undergrowth, it is misdirection."
NVidia has publically made dismissive comments about a 256-bit bus as if to cause people to think that the NV30 won't have one. They have also said they focused more on computational efficiency rather than bandwidth efficiency this time. On the other hand, several NDAed people have said that the NV30 has a 256-bit bus. Why make dismissive comments about a 256 bit bus if they are implementing one?
Now we have NVidia several months ago saying "already taped out in May", and recently "just wrapping it up", so which is it? One motive for the conflicting signals is to confuse the PR/strategy departments of the competitors so that they can't have any PR response ready when NV30 finally launches, since they will have no idea of the actual specs and schedule. This prevents competitors from doing to NVidia what NVidia has done to competitors in the past, which is release a PR blitz on the launch date of a competitor's launch to try to steal some of their limelight.
In any case, I just don't see why G, D, and H are arguing so much about NVidia's schedule. If they get delayed by a few months, what's the big deal? It happened with GF3 and GF4. If they do make it on time, you'll just end up with egg on your face having wasted months arguing it couldn't be done.
Are you just secretly hoping with every once of your persona that NVidia fails? So you want no competition for the R300 this fall so ATI can overprice it?