[quote name='rybrad']How long is an average game? I am going to pick up the Civ expansion during the Steam sales so I would probably only get a little bit of time in with this before then.[/QUOTE]
Honestly it varies widely. So basically for any map you set the size of the map, the number of opponents, and other things like that.
There are also several winning conditions, defeat everyone, cast a "unity" spell, control so many holy locations, defeat the avatar of a god you've angered, etc.
The games can go pretty quickly if you go with a smaller map and only one or two opponents. Even with more opponents and and a smaller map can probably do it in a few hours. When you start doing more opponents, on a huge map, and you are trying to go for alternative wins (wiping everyone out is the easiest, or was, not sure if they changed that in the update), then those games can really take a long time. It's one of things I liked is that you can customize the scenario's pretty well. I think that is one of the reasons they don't have a campaign, to be honest the lack of a campaign was the only real downside I saw....that and the whole "new feature patches" breaking other things.