I really applaud your recent announcement to have per-site Metas from now on for Super User and Server Fault too, as well as migrating lots of questions from here over there accordingly already.

Now, I'm pretty sure you have thought this through several times already (haven't found any recent discussion of this though) and are in fact explaining why your are not doing the same for Stack Overflow itself:

For now we are leaving meta.stackoverflow.com grandfathered in, as-is, with no changes; it’s still a standalone community with a standalone reputation system. We think Stack Overflow is large enough to justify this, and it just so happens that Stack Overflow is also the name of the company, too. Meta Stack Overflow will serve as the “National Capital” where we process feedback not just for Stack Overflow but for the core engine itself — while the smaller meta sites are akin to regional or state capitals.

These arguments are understandable and justified regarding having a “National Capital” where we process feedback [...] for the core engine itself as such, and having a standalone community with a standalone reputation system for this very purpose is probably just fine and not the issue here.

However, I still don't get why this means keeping this lone inconsistency and staying at odds with the Principle of least astonishment for all future users of the Stack Exchange Network (and we all hope there will be millions, aren't we?) by sticking to meta.stackoverflow.com rather than making the obvious switch to meta.stackexchange.com and migrating Stack Overflow only related question back to the thus free per-site meta.stackoverflow.com afterwards, just like for Super User and Server Fault right now?

I think my point is obvious, and I'm ready to take the potential downvotes (though I don't think these will be necessarily, a polite argument, or even just a 'because we wanna' will be sufficient, I can't and won't argue about that ;) - still here are some arguments in favor of the switch:

• As outlined already you will gain a consistent Meta experience within the Stack Exchange Network from now on for all future users.
• You will gain consistency with your section Proper Use of the Stack Overflow and Stack Exchange Name as outlined on the legal pages:
• You'll have Stack Exchange [network|sites|API] and, a perfect match, a dedicated standalone community with a standalone reputation system for all things meta regarding these entities.
• The poor homeless posts living on meta.stackexchange.com right now would finally find a new home, where they will be most welcome and just feel, well, at home ;)
  [I realize there might be some issues for sites staying on Stack Exchange 1.0 eventually though]
• The diamond moderator shoot-out regarding Proper location of Meta questions might be easier to resolve as well in the long run ;)

Well, I'm going to bed now and hope my morning coffee will be strong enough for the outcome of this instant questioning into the most recent decision of the Stack Exchange Pantheon ;)