If they do a significantly long day/night, I wonder if they'll make them proportional in length? You know, how day is longer than night. Also, I think seasons would be cool.
Personally, I've never liked the whole "you set the time" thing. By giving people the option to jump right to what they need to do, you discourage exploration and turn active tasks into grocery list items. You plan to do an exact thing, pop to the convenient time, do it and move on. That's not...
Something that might be neat is the idea that day and night affect the difficulty of some dungeons. See, the circadian rhythms of some animals would dictate that they either enter or leave a cage/dungeon during one part of the day or another. So for instance, bats/keese would be present in a...
I like the idea of a day cycle of about 40 minutes or so. it gives you time to play with dynamic events, but it also gives you time to have things happen in them and have the player find them, without just a window of a few real time minutes.