I’m not understanding this 3.0 talk

There seems to be an increasing amount of talk about “Gnome 3.0”, most
recently in comments by Luis and Dave.
It’s very puzzling. Reading these comments sounds like we’re somehow
failing or not progressing if we don’t do a 3.0. Yet none of the
comments seem to say that “here is something that we need in the
desktop and that we can’t do in 2.x”. In fact, many such comments
seem to state a bunch of things they’d like, but typically all the
concrete things they list can happen (at least to a large extent)
within 2.x. If I understand correctly, the reason for doing Gnome 2
was because there were a lot of concrete things needed that didn’t fit
in the 1.x framework. If we don’t have anything like that, and given
that work on a 3.0 would take a long time without shipping anything
and prevent people from getting as many incremental developments on
2.x, why would we even want to work on or think about 3.0 at this
point in time? Granted, I’m all for people experimenting and doing
cool stuff. And when we find something that’s cool that we don’t want
to live without and doesn’t fit in 2.x then we can work on a
transition. And I think that’d be good. But I feel like I’m missing
something fundamental because I don’t see any such things yet I see a
bunch of other people talking about 3.0 anyway. So what am I missing?

Also, Dave, you state that the 6 month cycle has outlived its
usefulness, giving the reason that 6 months are to short to get any
big user-visible features in a release cycle. While I agree that such
a time is too short for developing a big user-visible feature, I don’t
see why that’s a bad thing–big user-visible features can be developed
over multiple release cycles and then merged when it’s ready
(e.g. Luminocity and spiffifity). That even has the benefit of having
a shorter wait before officially shipping when it finally is ready.
Do you see the 6-month release cycle as just being to short to do the
final merge and testing of such features or something?

I have the feeling I’m missing something obvious that others are
seeing, but I really don’t understand a lot of what I’m reading…