Ceton updated their InifiniTV CableCard software last week to allow for tuner sharing between computers. Basically one computer can now relinquish some of its four tuners and other computers on the network can take the signals.
Setting it up wasn't too difficult but for some reason my video card was listed as non-compatible. The only workaround seems to be recording each show I want to watch and then watching on a slight delay. No channel flipping. I'm hoping its just that I'm using a DVI cable instead of HDMI. Its very annoying to have been waiting for this update only to not be be able to use it right because of an outdated video card. I'm not interested in getting a new video card either, the last few generations have been minor refreshes and major improvements are supposed to be coming in the cards due out in a few months.
Update: Looks like the HDMI cable did it.