I'll second that...FIOS On Demand is not up to par. As another poster noted, the CW is not on On Demand (OD). And I've noticed shows that were broadcast in HD are only available in SD on OD.
In general what shows are available are completely up to the various Networks. In this case it would seem that CBS is holding it up. Occasionally its the actual program owners, e.g. the Amazin' Race wasn't available until the last year.