A myth that we can bust is that you don't need to get your plasma screen re-gassed. Infact you can't get it re-gassed, it's a sealed unit.
Up until 2003 the claimed average screen life of a plasma television was between 20,000 and 30,000 hours, but the latest generation last for in excees of 50,000 hours - That's a lot of viewing!
The engine that drives the screen is very important, look for something like a XD engine, this means it processes the image to improve the quality for the screen.
Plasma televisions are actually cheaper than standard televisions, a 42 inch CRT would cost more to buy than the same sized plasma screen!
Plasma screens are not a new invention, the first was actually built in 1964 at the University of Illinois.
A lot of the actual Plasma panels are manufactured by the same companies so you will notice the same plasma specification for a lot of different televisions.
Most plasma screens can be wall mounted for that designer look and feel, not all screens come with a wall mount bracket included though, so ensure you check and order one if required.