I don't think that will happen though, there will always be a need for storage. I am surprised that camera makers haven't embraced much in the way of wireless technology though. I mean, really all it would take is to share a bit of wifi and 3G cell phone technology to bring these DSLRs up to snuff. If cell phones can integrate cameras, then surely that can be reverse engineered.
Jack is right. Average Joe Consumer isn't going to pay upwards of $700 for this technology. It's already on every street corner. The idea of being tethered to a cord while shooting in a studio is so...1990.