The Beta for OCS 2007 is out and I just got done attending a two day long hands on lab in San Francisco going over all the feature and functions and getting them up and running. I must admit I am impressed with some of the integration and work that Microsoft has put into this product. Granted the list of missing features is big ( there is nothing on the roadmap today to support the concept of a stand alone device that has no user associated with it - like a phone in a common lobby area or kitchen, voice paging, music on hold, and some other standard telephony items) but some shops will be willing to work around those issues to get the rich environment that Microsoft is pushing.
You can get the beta software here: The Power of Unified
So, what is Cisco going to do with their presence solution now is the real question. I honestly think Microsoft entering the game will help push along funding and research within Cisco which is a good thing. While Cisco has been interested in UC presence + voice it hasn't done the sort of serious push behind it that other Cisco products have had as of late. It deserves more attention and investment IMHO.
To top it all off I have already been asked a bunch about Exchange 2007 UM and OCS 2007 integration vs Cisco Call Manager and Unity + CUPS. Plus, some folks are considering doing some weird hybrid approaches or small test deployments. For those VAR's and partners who don't know both sides of the fence (Cisco and Microsoft) they will see their business value erode due to lack of technical knowledge. Hate to say it but I am going to have to brush up on all my Microsoft Exchange skill sets again!