At the Fleet Center in Boston, we've installed 6 plasma screens. Depending on the manufacturer of the plasma screen I would wait and see how the bracket to support the tv is made. The Sony bracket has a nice hole in the middle where you are able to pull your low voltage wires out and keep them hidden. On our installations we also mounted a receptacle in the wall at he corner of the screen where the power cord connects. I would recommend a clock outlet for this. A clock outlet is recessed into the wall giving you a little more room to plug in.

To center the plasma bracket we removed the sheet rock correspondig to where the mounting holes of the bracket were. we replaced the plaster with plywood allowing us to center the screen in the room. It is possible the plymood will getin the way of wher you are running the cables. You can mount your power and low voltage brackets to the plywood.

Good luck and feel free to ask any questions. Jim