[peterwwillis]

I agree except I don't think continuous deployment necessarily means automatic deployment. Every deploy should be done by a person and tested right after; none of this "push out all commits at X time" or "push as soon as it's committed" as both are risky.

During the day is usually preferred and never at 4:59PM on a Friday or right before everyone goes to lunch (ever had to clean up a downed cluster when some jerk pushed bad code and the whole team went to Sweet Tomatoes? yeah).

To help troubleshoot breaks, have a mailing list with changelogs showing who made a change, time/date, files touched. Also have your deploy tools mail it when there's a code push, rollback, server restart, etc. Have a simple tool someone can run to revert changes back to a time of day so if something breaks just "revert back to 6 hours ago" and debug while your old app is running (nice to take one broken box offline first to test on).