According to a recent post on the MediaMaster blog http://blog.mediamaster.com/2009/01/13/power-outage-for-mediamaster/ the service has been suffering from a string of recent power outages.  MediaMaster is probably the slickest of all the mp3 music storage and hosting services.  As I know from personal experience the business is pretty tough and they may be going down the road of paid for accounts soon.  If you haven’t checked them out yet, I high suggest doing so – that is when their website is back online.