yeah, we'll try to shoot for 2 hours in the future. I think that's a good idea... however, my topic suggestion might keep us talking for 7 hours or so. :D
And yes, time frames would be good. I think maybe 15 minutes might give more time to get into in-depth topics? I've been in hangouts where the topic is 5 minutes long, and it's just not enough. I fear 10 minutes might also cut things a bit short. I may reconsider if people start flooding these threads with suggestions. lol
I like your calculation idea...