I am a subsriber and wish I could answer your question. But being I am signed up for the 8 out at a time program I never really have to worry about "High Demand", "In Demand". With the yearly program I always have something coming and going. My advise is, upgrade to the yearly service and you will be much happier. :)
giveme, on the FAQ page they have an explanation of what the terms mean. BUT, don't take it as gospel as I have had Hitch with a short wait shown in my queue since 7-6-05 and it has been passed over many many times to have something filled from below. My Mother used to always say that patience is a virtue.
Example: I've had Napoleon Dynamite in the number one or two spot with a "Short Wait" tag for at least 3 or 4 months. Yet, it gets passed over all the time. Even a "High Demand" item will at times get sent out before the others.
All this is not a real big deal to me, though I'm sure it might be for others.
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