For three days or so, every entry I've posted (about 20 so far) has duly sent a ping to MT, and every one has come back with this:

Ping 'http://www.movabletype.org/update/' failed: HTTP error: 404 Not Found

Is there something askew at Six Apart's end? My key seems to be correct. (This is version 3.21, if that matters.)

They know and are supposedly looking into it.

Any word on this yet? It looks like some people are getting their updated blogs shown on the MT site. I can't stand the thought that Six Apart shut off this service for early supporters (of which, I am one). But, I'm starting to wonder...

Last time I asked for an update to my ticket they had not heard back from whoever is in charge of that part. It might be nothing, but like you I am starting to wonder just a little bit.

Heard from Shelley and it turns out to be nothing (almost). Apparently someone did some cleanup on the old movabletype.org and didn't realize that it was still in use since everything is sixapart.com/movabletype now. We're still in the game