By pelegri on Jan 19, 2007
On the performance side, Ryan reports on measurements of tps under client (state is kept in the HTML sent to the client) and server (state is kept in the server memory) mode and both cases show very nice improvements, specially when using multiple processors. The best description I found on the tradeoffs between client and server modes is this blog by Jacob; as a simplification, server is faster while client uses less memory.
More entries related to JSF can be found here.
Added: Also see this Section in the GlassFish Wiki.