The death of the shapefile has again been predicted---this time for 2010.
The technical description of the format has been around for going on 12 years. In that time it has become a sort of lowest common denominator for data exchange. They're everywhere. Making them go away is going to require a revolution of sorts.
ESRI has been sounding the death knell for the shapefile for a while now. I agree that it isn't a perfect format but it is nearly perfectly supported.
If ESRI really wants the shapefile to go away, they will produce a fully open API for the File Geodatabase---one that can be used outside the Arc* realm. One that can be obtained and used at no cost or license fee.
There is a raft of open source programmers waiting in the wings to code against it and provide support and interoperability for the open source GIS world.