As a regular user of the monkeysphere, you probably want to do a few things to make sure that you get automatically notified of any re-keyings or revocation of monkeysphere-enabled hosts, and that your keys are properly managed.
Keep your keyring up-to-date
Regularly refresh your GnuPG keyring from the keyservers. This can be done with a simple cronjob. An example of crontab line to do this is:
0 12 * * * /usr/bin/gpg --refresh-keys > /dev/null 2>&1
This would refresh your keychain every day at noon.