I am trying to decide on whether I should get a 16GB or a 32GB. I would rather spend less money and my main use for the Touch will be the Apps and keeping Calender, ToDo, etc synced with my Mac. What size are App Store apps on average?
From what I've seen most games are under 100MB. Applications vary more but there aren't many that are huge. You'll more often than not find them under 50MB.
Of course, I haven't looked at everything yet. I've seen some at around 300MB too.