I am sure most of you know this, but I figured it was worth posting my results now I've actually tried it.
We have a games room with a 42" Samsung plasma. Picture is very good, but the sund from the nternal speakers is so bad that I honestly think they would be better off selling it without sound at all and letting people add on. Anyway, I placed a BeoSound 8 under the TV, and connected the headphone jack to the phono in.
Excellent sound quality, volume output is still controlled from the samsung remote, and the BS 8 turns on and off when it connects the TV input. With a PS3, and apple Tv connected to the TV I get sound from all through the BS8 with no messing, and so can airplay from an iPad/iPhone direct to the Apple TV. If required you just stick an i device in the dock and that over rides the TV and instant music.
A brilliant solution, which outperforms any soundbar I have heard, with the added bonus of being able to dock a device directly. If marketed as such I rekon they'd shift bucketloads.