It's just that it's hard to put into words. It's something you have to see to understand, and even at that, you need to be into film/video to care one way or the other. I majored in film production in college, so my eye is attuned to things like image clarity and film grain. I was trying to explain the difference to my mom and sister tonight and they couldn't relate to what I was talking about.
As far as the TV's involved, both are 42" LCD, hers is a Vizio and she paid about $900 where mine is Westinghouse and I paid $600.