As long as you're not a non-rever, once that boarding pass has your F seat assignment printed, it's in your possession, and you're in your F seat, you're an F passenger entitled to all the perks and privledges due you.

As long as you checked-in prior to that other F passenger, it sounds to me like you were a F passenger involuntarily bumped...and you should be entitled to a form of denied boarding compensation. Rather than go by last-to-be-cleared, they should have gone by check-in time to determine who should be bumped.

Kudos to you for keeping your cool --had that been me, I would have raised hell regardless of the day. I would have demanded a "red coat" or equivalent on the plane and asked them what DBC they planned to offer for the inconvienance.

As far as what you should do now, you should write to Continental. I think a call to the 800# will just leave you more fustrated.