Om has a post that includes comments from Burton Group Analyst Irwin Lazar about Enterprise VoIP and how Microsoft enters the equation.
I think that the Enterprise is where the money is. AT&T is clearly headed in that direction. With the SBC merger one has to realize that SBC is already working with Cisco as an integrator. Now add in AT&T as the network and layer in their technology, like they showed at VON last week.
Now what about Cisco? They become nothing but a router company with one heck of a sales force and distribution channel that gobbles up sales leads and converts them better than anyone.