I've some questions about the presentation stuff:
1. now that we have explicit messages for presentations in the protocol, can we remove the bridge thing? Yes, I know that presentations will then not work with the dedicated output stream, but that's a efficiency hack and layerying the bridge kludge on top of the efficiency hack is so ugly, it makes me cry. I'll remove it, if there are no objections.
2. is there another way to handle presentations than with after-change-functions? Our after-change-functions are totally broken in Emacs20. Could we use overlays instead of text properties for presentations?
3. is *can-print-presentation* still needed? It seems to me that slime-stream-p serves about the same purpose, but it is much cleaner. It's also ugly the we need to bind *can-print-presentation* in a lot of unrelated/random places.