Many thanks for your responses!
My plasma sits about 3 feet behind my speakers - but even at that distance it hinders the soundstage. My situation may be worse than others because i use large planar speakers with bi-directional ribbons. A quick check last night with throwing some towels over the screen showed enough improvement for me to take this project very seriously.
I will check out the foam and comforter options locally to see what can be done.
Cheers.