My understanding is that plasma fares better at off-axis viewing angles (from the sides or above/below) than LCD does. I know that dad's LCD looks pretty washed out of you watch it from their couch (probably 45 degrees from the side), but it does a much better job straight-on. That was one of the main reasons a co-worker of mine went with plasma last fall.

I suspect that stores are pushing LCD so much because LCD has seen such a significant price drop lately, making it sort of the "hot new tech" - while plasma's been comparatively stable on price and screen size. Plus there's no need even to bring up burn-in with LCD, although what I've been reading for the last year or more suggests that plasmas have really improved in resisting and preventing burn-in.