I believe I fall in that 95% category that has no clue(even though I thought I did).
I'll say though that the salespeople at these retail stores know about as much as I do, as I specifically asked if the tv I bought had the digital tuner. I was assured that I would be able to receive OTA digital signals(as all the tv's that were described as SDTV's also said they had digital tuners on those little desription cards). At least 6 of the 24" and smaller tv's labeled as SDTV's also said they had digital tuners.
I also find it amusing when I called later that evening to talk to the assistant store manager, they had no idea about the Mar 2007 deadline for all tv's to include digital tuners. All I heard was, "I've never heard of that" and "I'll have to check that out", followed by a seies of loud sighs as I tried to explain.
Frustrated and confused