The other day I was in a supermarket chain looking at a 40" Sony TV playing a SKY satellite promo. There were two pictures in split-screen (left hand was SD, right hand was HD).
I looked close at the SD picture....it had been doctored to look worse than what it actually is. It had been put in soft focus so that your eyes went right to the HD picture. That is a filthy trick to make you buy a HD satellite box and I won't fall for that old gag and any TV engineer looking at that picture would have said exactly the same thing.
You have to give them points for trying I suppose