Garmin updates firmware for 60C/60CS/76C/76CS
Garmin has released a minor update for firmware for the 60C(S)/76C(S) units.
What they list as what has changed from v3.70 to v3.80 is:
Go to http://www.garmin.com/support/download.jsp and select your appropriate model, though the firmware for all 4 units is the same.