Rejaw is a new way to communicate in real-time with friends, family,
and co-workers. You can shout messages to your followers, or whisper
to your friends. Monologue or dialogue, micro-blog or status update,
soliloquy or dialectic – how you use Rejaw is up to you.
It allows you to embed images, audio, and video as well. Pretty much a
drop-in replacement for the now defunct Pownce.
Not sure how aggressively you guys are looking to add services, but
whenever you get around to it...
Here are the API docs:
http://code.google.com/p/rejaw/wiki/API