You may be confused by the new connections that are used from a HDTV "box" to your HD TV. You'll see HDMI and other cables but so far COAX isn't used since that is used for SDTV or from the cable co to your HDTV "box."
I was looking at coaxial cable for a TV installation. The store had both the old-style & a newer version (more expensive) that is indicated for HDTV.
Is there any real or appreciable difference between the capabilites of the cheaper & newer coaxial cable? And if so, does this newer, better cable just have to exist in the run from the source (HDTV box) to the television itself?