At that point I got busy with other things (most notably final preparations for the FreeBSD 9.0-RELEASE announcement) but on Sunday evening I sat down and wrote a much-needed shell script:

# ssh-knownhost hostname [fingerprint ...]

The ssh-knownhost script uses ssh-keyscan to download all the host keys for the specified hostname; uses ssh-keygen to compute their fingerprints; compares them to the list of fingerprints provided on the command-line; and adds any new host keys to ~/.ssh/known_hosts. Short, simple, and effective.

Could be really handy.