Thanks for that link.
I don't know much about this. It refers to a pair of cat 5/6 cables to HDMI plug plates. Does that mean there are two sets of wires that end in a single HDMI plug? Does one wire carry sound and the other picture?
No, it is digital, so one carries zeroes and the other carries ones.
HDMI doesn't work like traditional A/V wiring, there is a lot more than audio and video, and none of it is analog, so it works differently.
For wiring, you should run CAT-6 wiring in your home and pull at least TWO pieces of CAT-6 to every location where you want to connect HDMI to. I would STRONGLY recommend that you run conduit as well so you can add component later if you need it.
I am using the Monoprice cat-6/HDMI adapters listed on the link above (2 of them) to connect my PS3 to my rack, to an HDMI splitter, to my projector and plasma. Total length of run: About 110 feet. I used prefabricated CAT-6 cabling from Monoprice...
http://www.monoprice.com/products/product.asp?c_id=102&cp_id=10232&cs_id=1023213&p_id=2325&seq=1&format=3#specification
But, you can use raw cat-6 and terminate it yourself...
http://www.monoprice.com/products/subdepartment.asp?c_id=102&cp_id=10234
You just take two pieces of CAT-6, terminate it normally (568B), and plug it into the back of the HDMI extender on both ends (transmit/receive) and it works well.
I have several more that are going to be installed in my home and I may end up pairing it with a 8x8 HDMI matrix switcher to see what I can really get out of HDMI in general.