I just recalled another multi-room solution. Most houses have lots of Cat5 or CAT6 wiring these days. You can purchase HDMI splitters/extenders that run over CAT5 or 6. It used to be that you needed two CAT5/6 runs but when I went looking for a link for you, I discovered that there are now models that require only 1.
I can't speak to this particular model, I link it only as an example. HDMI via Cat5
I will actually be experimenting with some type of these soon as Sharon is looking to get a TV for a room upstairs where there is coax but I'd like to also have it hooked to my central receiver in the basement. That way, It can be used with HD from any of my sources as opposed to just SD from the Satellite dish.
Man, I'm so glad I put in two separate power circuits to my AV shelf area. I'm soon going to need to invent cold fusion to cut back on my electric bill from this damn hobby.