Of course, that short little bar that represents Oct 2005 -> Jan 2006...yeah, that's be when I bought my 20" iMac G5 w/iSight. The guides don't always work. The iMac line upgrade standard deviation is very large. I think they must upgrade the line every time Steve sneezes.
Depending on how they do it, a major new feature such as religion may not add too much to the complexity of the game. If you've played SimCity3, you'll know what I mean. They added garbage collection in addition to the earlier electrical and water distribution mechanisms, and it was something that was easily learned and handled. Civ4 may handle it equally nicely.
No, I'm just out of the office this week.