[HiveLordJim]

I host PBEM games and have had the computer take 20 minutes to process a turn:
11 years into the game, 10 empires left from 17, multiple fleets of 50+ common with a 500 ship per player limit.

The game will seemingly stop for 3 mintues then the progress meter will go up a percent.

I have had the game hang on 2 occassions. These hangs were because of some weird bug with fleets that malfador said they were fixing in the next patch.

Hope that helps