Only just came across this - someone's done a video featuring gameplay and commentary about the demo. They like the game overall, thought the menu screen and scroller was hilarious (!), and dissed my voice acting. A fun look at how people's thought processes go through the game's puzzles, and how we've missed some things that are fairly obvious completely passed us by in the development process.
He got nowhere near completing the demo in 15 minutes (which is a bit of a relief!) - I think 45 minutes is the best guess at average time to complete it.
If you haven't played the demo yet, you can download it here.
Tomorrow night we'll find out if we've won in the Best Demo category of the AGS Awards 2012...