Let the hive mind of Engadget get that for you.
"What is the best wireless surround sound speaker solution? I have a home theater where running wires is just not feasible. I have my own speakers, so I don't want a system that has speakers with integrated wireless. I've done a far amount of research and have only come across a few companies that even offer a reasonable solution: KEF, Kenwood and Rocketfish. Is there anything else out there? What do you recommend? Thank you!"
Cost, Efectiveness, Price. Replacing (almost) all your cameras like ESPN has done, isn't cheap. Also its mostly because alot of stations don't see the need to do so. That's why the federal goverment stepped in with the DTV by 2009 and the extra cash the goverment will make off of it helped them decide that too.