If you missed it earlier, I recently completed a similar series on VoIP for business, and you can get the links here for those posts.
This is the first post in a three part series on UC, starting with how we got here and what problems UC is trying to address. Following this will be an add-on piece from another contributor that helps decision-makers evaluate specific offerings, so watch for that as well. My kickoff piece was just posted yesterday, and I hope you find it helpful. Stay for Parts 2 and 3, and along the way, any sharing would be greatly appreciated.