Despite Microsoft’s grand pronouncements that its unified communications launch signals a revolution in the way corporate workers interact, users and experts alike say the conversion will be a slow evolution that includes careful planning, budgeting and management.

At Tuesday’s event in San Francisco, Microsoft not only formally launched its unified communications (UC) platform anchored by Office Communications Server (OCS) 2007 and Office Communicator 2007 client, it also introduced the centerpieces of its unified communications strategy to bring together e-mail, instant messaging, presence, voice and video.

Microsoft chairman Bill Gates, who kicked off the event, signaled that the UC platform was the beginning of the end for the monolithic and inflexible PBX. He said OCS and the UC platform were all about taking the magic of software and applying it to phone calls.

But while voice may be the most interesting component on the UC platform it is by far the most complex and likely the last to make it under the fold.

Voice, however, is not the only lingering question about a set of services that also revolve around integrating e-mail, instant messaging, presence, Web conferencing, and video so they can be tied into business applications and workflow processes. Experts say corporations aren’t facing a single decision on UC, but a series of decisions that hopefully add up to what is promised as a Holy Grail for corporate communications.

“The biggest thing with IT goes back to the governance issue,” says Mike Gotta, an analyst with the Burton Group. “How do I put the program together because this is not a project; it is going to be a three-year program. Users have to get the desktop team, the collaboration team, the [unified communications] teams, they have to get the compliance people involved, they have to work with the business units on decision rights, they have to determine how much of this is centralized, how much wiggle room do the line-of-business units have, there will be touch points with wireless carriers, there are a lot of pieces so the biggest thing is organization and governance.”

Gotta says picking vendors also will be complicated as Microsoft and IBM are engaged again in their traditional collaboration battle, but there are also options from network vendor Cisco and traditional telephony players such as Nortel, Siemens and others.