UCC API Released!
The UCC API (Unified Communications Client API), formerly UCCP, is finally released! This differs from UCMA in that the UCC API is meant for client applications, such as building your own IM client and UCMA is meant for server side applications, such as bots.
http://www.microsoft.com/downloads/details.aspx?FamilyID=82c468da-3294-4ca9-bbcc-d455cfd06af2&displaylang=en
The UCC API isn't a replacement for the Communicator API, but it really seems to replace the RTC API. So if you are have exisiting applications which use RTC, you could use UCC API instead. There are some gotchas such as the UCC API doesn't have support for Peer to Peer like RTC has, but if you are targetting your application to hit an OCS deployment anyways, you aren't going to want to use Peer to Peer anyways.
I'm will be working on some UCC API samples and will be blogging about it probably mid November as I am currently swamped with projects right now.