yes, it is hdmi over ip. I prefer the Vanco brand, but price is considerable higher. I installed the Mirabox about 2 years ago, an still works fine. Remember, if you have two or more sources for distribution around the house, the options could be more complicated/expensive. That means you may need a matix switch with several inputs (sources) and multiple outputs (rooms). The Mirabox solution could handle from a single input (tivo) to multiple (tv's) outputs, just by adding multiple receivers (remember using a gigaswitch
cat5/6 to all room, in that particular network). Let's say all tv's watch tivo in hdmi-1. If you need add cable to all rooms, technically adding a separate Mirabox network (one transmiter to multiple receivers/rooms), using a separate gigaswitch, an using hdmi-2 for watching cable, should work. You still need to figure out a way to change channels via IR receivers (normally a matrix switch takes care of this task). Not sure if Mirabox have another model which includes IR control over the same cable (I included a video from a different brand, but no experience with it). Let me know if you have any question, but I will recommend to keep it simple. Just start with a couple units (tivo for two rooms + ir control)
Good luck.
Mirabox;
another brand with IR, good source of general info: