Also thinking about it: I guess we'd want to make the usage of libslirp optional, at least because (I guess) at some points the future libslirp may want to change the API (nobody can do something perfect at first try), and when that breaks qemu build it would nasty if people couldn't just disable libslirp usage to get qemu built for needs which don't require slirp.
Also some people would really like to see the dreaded slirp stack off their qemu binaries :) Samuel