Tom Keating has an incredible review of Microsoft Unified Communications products which has yet to be posted. I believe there is an embargo until later today. I really suggest you check out his blog regularly until it hits. I read the draft of the post last night on the plane and was blown away by the level of detail and sophistication in his writing. It is everything you need to know about Microsoft unified communications.
Also be sure to check uc-mag.com throughout the day for full Microsoft unified communications coverage.