The time it takes to idle out from the game has been increased from 15 minutes to 60 minutes. This should help avoid frustrating situations where you have to step away from the computer for a short time and don't make it back before the idle timeout.
The online list now also has a color-coded "idle" column to show how long each bot has been idle. With this list now potentially showing bots that haven't been active in close to an hour, this will help give you a quicker impression of which bots are truly active at any given time.
Thanks to Agent Zord for the suggestion!
P.S. Fun trivia fact: The idle timeout in bots2 was 10 minutes.