The good news is that my WCF system to manage multiple Media Center boxes from WHS is almost finished. The bad news is a gotcha I just ran into when testing with Win 7 and QAM:
I'm trying to build a list of mapped channels (permitting, in the absence of EPG data from within Media Center, scheduling by time and channel with dropdown lists). While this works quite nicely on my old Vista and my Win 7 Cablecard system, it's not so hot for my Win 7 QAM system; getting the mapped channels via Lineup.GetServiceIds returns only the major channel number. Indeed, in the MSDN documentation, it even states "This method does not support sub-channels. For example, if there are sub-channels such as "4.1", "4.2", and "4.3", only "4" is returned with the service ID of the last sub-channel."
So how can I provide the user with the proper subchannel information to permiit him to create a valid Click2Record request?