This ad is typical of what you find from some retailers, particlaur the big box shops like Best Buy where the marketers get the better of common sense.  This one is actually flirting with truth in advertising issues and is certainly guilty of exaggerating, if not guilty of some worse infraction for lying to customers.

I picked this up from the HDBeat, a blog on the topic of Home Theater except this one gets traffic.  To simplify the reason this is a lie, their rating of 1024x768 is not really HDTV.  1024 lines of verticle resolution isn't enough for HD.  It's higher than NTSC, but this isn't a 720P set, this is what's called EDTV (enhanced definition) not high definition.  If it seems like a fine point, actually it is because there is a body called the ATSC that has placed real world definitions on what is and isn't HD.  So, basically you're asking for a car and they're giving you a rickshaw. 

Here is Magnavox's online profile of this set, they know its not HDTV and they call correctly call it ED.  Someone should let Best Buy know.