I'd like to point out that it wasn't a first date. We've been going out for 25 years (yes - the FrontLine partnership is that old). You mention PCs and printers; but we also have the largest market-share in servers and storage that power Microsoft products - which I'd hardly call the 'scraps'. Providing a platform for Microsoft OCS in the branch office helps to build the case for more HP infrastructure in the branch, and supports the sales of network, servers and storage in the data-center.
HP’s joint initiative with Microsoft spans multiple business units, and was reinforced for Unified Communications with the $180m announcement last year at Interop Vegas (Microsoft press release, NoJitter blog, video).
The other key theme I picked up from the show was the need to relate the technology to business value, and to integrate UC into real-business processes. HP, as the worlds 2nd biggest services company has a role to play here as well. (Check the discussion I had with Steve Grumann on HP's business value services)
You can read more about the areas of collaboration we demonstrated at VoiceCon on the HP Networking blog.
I agree with Dave's other points. Whilst desktop video is ready from a technology perspective; I don't believe that any large companies have started rolling it out in anger - due to concerns over network utilization. There were a couple of good quotes on the subject on a NoJitter post from Brian Riggs - “Use of video conferencing over OCS has resulted in such an increase in video conferencing that Stoneridge is now obligated to upgrade its network infrastructure” and from another customer - "We just threw buckets of bandwidth at everything."
Obviously I can't say anything about 3Com while the acquisition is still in progress.