Mention the "README.{system}" files.
Supply all the URLs for the 1993 Winter USENIX paper, including those on
tcpdump.org.
Give all the names DEC OSF/1 has gone through in its life.
Mention that Linux, in 2.2 and later kernels, has a filter mechanism
that supports BPF.
Mention the SourceForge site.
Update the note on libpcap being "not very well suited for interactive
programs" to note that at least some of what it says is necessary is
already supported.
guy