I got this email from Pownce today.

We are sad to announce that Pownce is shutting down on December 15, 2008. As of today, Pownce will no longer be accepting new users or new pro accounts.

To help with your transition, we have built an export tool so you can save your content. You can find the export tool at Settings > Export. Please export your content by December 15, 2008, as the site will not be accessible after this date.

Please visit our new home to find out more:
http://www.sixapart.com/pownce

So Pownce was bought by Six Apart (the Moveable Type people) but it’s a little unclear (to me at least) what will happen to the technology, it seems like it will be integrated into some Six Apart products at some point in the future.