For anyone who's interested, a lot of people have been having issues where their keyboards will stop working and have to unplug the keyboard and plug it back in to work. The media keys will also sometimes stop working and will start working by themselves. I've found a thread on Apple's discussion forums relating to this issue. It seems there is no resolution to the problem but it might be a software issue. Here is the thread from Apple.
http://discussions.apple.com/thread.jspa?threadID=340067&tstart=0
http://discussions.apple.com/thread.jspa?threadID=340067&tstart=0