Plasma are more susceptable to screen burn compared to other display technologies but the broadcasters point the finger at the manufacturers and there is only so much you can do to protect a plasma display. However SKY are only to blame for their own logos, the BBC, ITV, CH4/E4, Hallmark, Scifi etc etc all choose to use the damn things.
Same goes for the interactive logos I am afraid but at least they can be removed on a semi-permenant basis or totally when using SKY+.
You'll find something of interest over at the
Logofreetv website.
I appluad the efforts of these dedicated people but once the BBC slapped logos onto their digital channels any chance of getting commercial broadcasters to follow suit is pretty slim.
However I have huge respect for the person responsible for ditching the CH5 logo when they rebranded as Five, gave the channel a much more mature and professional look.