I rarely use the stereo system with the tv. I've got HDMI running to the tv from the cable box, the PS3 and the blu-ray. All of them make both audio and video come out of the tv. I've got an audio cord running from the tv to the stereo so that I can kick on for extra sound for games/movies.
I've got it to work at the moment by using the HDMI for video into the tv, and using an audio cord with little headphone-type jack on one end and the split red and white bigger input things on the other running into the auxiliary on the stereo and getting my sound out of that. I'll either need to get really long cords of each type or get a wireless keyboard so I can bbs simultaneously.
Or Captain Crap can make some things happen to where K-StateHD.TV plays on the PS3.