Tivo put both marketing and customer service folks on the tivocommunity web site way back when (I think before it was called 'tivocommunity'). It was certainly a great boon to both the company and the user community, however it represents a significant time and resources expenditure. They have a handful of people who spend much of their day keeping up with posts and responding, and I'd imagine there are a whole pile of people backing them up.
Directv for the most part seems to want to run their stuff through the ordinary channels. Their directv.com hosted tech support site is not manned by directv employees, which I find totally strange. When their marketing people could have gone to a place like DBStalk or here to ask questions and do polls, they instead chose to do their own in-house private forum which would have been okay but the software was incredibly weak and lame.
Just getting someone to show up at the main public forums like this to read through some topics from time to time and take PM's would be a huge resource to a company like directv. Having them able to comment on things to answer persistent questions or explain things would be a huge resource to its customers.
But being presented with enormous opportunities doesnt seem to be creating any interest at directv. I'm guessing they like to limit customer communication to very specific channels and play things very close to the vest.