We have 2 one is Panasonic and one a Samsung both are Plasma. We bought one when the Beijing Olympics were on, the other a few months ago.
Deciding between LCD/Plasma/LED really depends on what you want to use it for and where in the house it is going (ie. lots of natural light? Room with more home cinema feel).
In terms of Brightness - LCD looks better in the shops and works better in a room with lots of natural light as it has a matte screen. Plasma looks better in a home theatre/darker room as it has a reflective screen.
LCDs have brighter more vibrant colours. Plasmas have warmer more realistic colours and truer blacks (higher contrast and detail in dark movies).
Plasmas are better for fast moving scenes, but better LCDs have now caught up so there isn't a huge issue with blurring like there used to be.
Generally they say though that for 37" or less LCD is recommend and for 37"+ Plasmas will perform better.
There is some good info here