My gaming group has been ruling that you may fight defensively or take a total defense, then move, and retain the AC bonus. I have always thought this was a house rule, one which I had no problem with, so I never disputed it, but I was sure that the CRB stated that you gained the AC bonus until your next action, not your next turn. However, looking at the PRD now, I see these definitions:
Fighting Defensively as a Standard Action: You can choose to fight defensively when attacking. If you do so, you take a –4 penalty on all attacks in a round to gain a +2 to AC until the start of your next turn.
Total Defense
You can defend yourself as a standard action. You get a +4 dodge bonus to your AC for 1 round. Your AC improves at the start of this action. You can't combine total defense with fighting defensively or with the benefit of the Combat Expertise feat. You can't make attacks of opportunity while using total defense.
So, obviously the current PRD specifically states that the AC bonus lasts until the beginning of your next round, and not until you take another action.
Was this an errata, or am I remembering the entry from the original CRB incorrectly?
Ok, I guess it is poor memory then. I will confirm tonight, though, as we are gaming tonight, and one of my friends has the first-edition printing of the CRB.