Barclaycard do not cover Plasma & LCD, just 'normal Tv's. However, if you have a Nationwide CC, then these ARE covered. I checked with them last week, just to be sure as I'm thinking of getting the Panny 6.
I tried to get a nationwide card...... despite having a £4k limit on my current card, never having failed payment, spend huge amounts anually with it....... they turned me down. Cant say I was well pleased about it. Nationwide claim to cover pretty much anything, but I suspect that their insurer may say otherwise on some more exotic items. Id suggest checking with the insurer directly and not nationwide themselves