Reading Williams' post reminds me of the advice that is given when making a presentation: Tell the audience what you are about to tell them, tell it to them, and then tell them what you just told them.
Williams thinks eight steps will do the trick: Sketch out implementation plan; determine a switchover point; announce it; implement UC technology at the server level; invite a group of users to test it; furnish all users with a training kit; evaluate alternatives; remind users of the switchover point; make the switch.
Note that half of the steps directly or indirectly involve communications with end users. It is possible in the busy and increasingly complex world of running an IT department to forget this vital element, which is making sure that end users are in the loop and onboard. This loop consists not only of knowing when the UC platform will become operational (though that, of course, is vital), but creating the feeling that their cooperation is important and they are gaining access to a system that will make their work more efficient and effective.
It also is important to make sure that the platform being created is optimized for those who will use it.. Unified communication is complex by nature. Once an organization decides it is serious about UC, a user group should immediately be formed.
Once this is done, IT and telecom folks should get as far away from this group as possible, except to gather intelligence. It is important that folks who aren't technically adept be asked to assess how they like the system and whether and how they will use it. The group should be varied and include everyone who will use the system in the short and long term, from folks in the mailroom to upper-level executives. The results will be valuable to those with ongoing design responsibilities.