That TV is the cut down version of the 42PX70 (which is the one I have and its utterly superb). As far as I know, the only difference is that it only has 1 HDMI input, which may or may not be a factor for you to consider.
The John Lewis one has the Pedestal included, and I think its exclusive to John Lewis as when I was shopping around (this is I think so they cant be forced to price match elsewhere), I didnt see that particular model anywhere else.... so first of all you need to be comparing prices with the 42PX70PED.
I got mine for about £600, but this was with a combination of a bank holiday deal which included extras that I sold on, and also a complaint letter for some poor customer service etc that got me further money back.
A quick check now for you :
Soundandvisiononline.co.uk £768 (free delivery)
Dixons £779.99 (can be reduced with a 5% code, and also quidco reductions)
Also check daily on
www.pricerunner.co.uk
There is still a promotion going on with the Panasonics that gives you a free 5 year warranty from participating dealers. Ive read that EmpireDirect is one that is in the promotion (because they have a store, and are not online only), but they are currently out of stock on the 42PX70. Check it out here
www.experiencewhatotherssee.com
You could also look at the Pioneer Plasmas, which along with the Pana's are the best around.