But honestly, it's just for the nostalgia. Most Civ fan's I've found really get into the mathematics of the game, essentially breaking down victory conditions to mathematically formulas with uncertainty left only to starting position and battle out comes.
Revolutions is a fun game, but it's not nearly as 'deep' and as such, limits the amount of interaction and opportunities you can have.
As a Civ fan, I wouldn't recommend purchasing the game. I think you'll get your fill out of 'discovering' the different options to win in a rental's period. (Online experiences may vary, along with ESRB.)
I'd frame the argument differently. Honestly, I'd recommend it even to die-hard Civ fans under one the sole condition that they really like online play (preferably fast paced). Online matches are definitely worth a try, IMO.
Apart from that, it's simply not as attractive to Civ fans as the regular console joe: There's simply only one way to win it and that's by military expansion - I know, there's multiple victory condition, but in the reality all will rely on military expansion. The gameplay isn't diverse enough. etc.