I'd say on average it's similar to being awake. In many nonlucid dreams, some saga will persist over several dream days, but I can't remember any such thing happening while I've been lucid.

It probably depends on the dreamer, though. Some with good dream control might be able to control the passing of time effectively and make it seem longer or shorter. My dream control is not that good. (Yet. I'm thinking of studying dream control more while I'm here.)