I answered 1 minute but for the most part it didn't really matter unless you were keeping track of time for some other purpose. Within the bounds of the combat, it really wouldn't matter if each round were 1 minutes, 10 minutes, or 30 seconds. Rounds were just tools to manage the flow of actions and the time could be perfectly arbitrary as long as they enabled you to pace out the actions the way you wanted to.
With respect to some actions, like picking locks, 1 minute rounds work better than 3e/PF 6 second rounds. With respect to trading blows in combat with a single opponent, 1 minute strikes me as way too long. Moving about a large scale battlefield, fighting a mook here and there where each is dispatched in one round before you move on to another opponent, the 1 minute works better.