Originally posted by goodbye_mr_bond:
The most important thing is to find your own style...
I think the super-science city's not that important, personally. I've been meaning to try it out one day, but haven't yet. Hasn't hurt my ability to stomp Zulu butt without it though.
Definitely expand early, and at every opportunity. Don't be too picky about terrain either. So your city will never be size 40--who cares? It's far better, especially at the beginning, to control as much territory as possible. I hate to leave even a single 'plains' tile open around my cities, as the AI will often build a city there, and that's more annoying than having overlapping tiles.
And Hippo's suggestion for 2 good def., 1 good off. in every city sounds a bit extreme--