Once you have done this you do need t obe careful what resolutions you choose as you may end up with the TV showing "OUT OF RANGE" or something. This happenned to me and I had to plug in a pc monitor to change it back.
On my plasma (native 1024x768) 1280x720 did not work, but 1366x768 did.
If 1366x768 does not show up as an option in graphics properties then you can use power strip to add it.
So... it is not plug and play but the result is worth it.