>So, will be go back to file-based data stores? Let me know what you think, and why one paradigm has an advantage over another.

As some point, client-server will always scale better than a file-server based system (less data going over the wire). Whether a given installation ever reaches that "point", is the question.

In theory, it's possible to design a client-server app where all traffic is basically one-way (eg. stored procedures that return no result sets); the same cannot be said for file-server, where every update has to occur on the client first (assuming no DCOM, etc ... which would imply "client-server").