TLS Guy, you aren't answering his question.
The correct answer to the question is this. HDMI pass-thru and HDMI switching are the same thing.
Less expensive receivers have HDMI pass-thru, or switching only. What this means is the HDMI ports are used just like any other video switcher, it takes video inputs, and has an output to a display. That is all they do.
HDMI repeating is a step up from HDMI pass-thru/switching. It still does the switching, but adds the ability to take the audio bitstream from the HDMI source. Such sources include satallite/cable box, upscaling DVD player, Blu-ray player, HD DVD player, PS3, or an X-box 360 (the newer that features HDMI output). Some of those receivers also have scalers, but I wouldn't get to excited about those.