I received RoN in May, I must admit that I was surprized in the good sense of the word. I'm very far to be a RTS player, it requires a too big stamina and adrenalin expense. Nevertheless I tried and in solo mode using the features of the game I found out it is possible to have fun and thinking in the same time, with an excellent sound track, a beautiful screen and this is a real pleasure, to complete a game in a short time.
The Sybex Strategy Guide is good and compared to the poor one issued by Prima for Civ 3 I can say it's an excellent book.
No way to compare RoN and Civ. I believe the both should be present in any gamotheque shelf and used as frequently as possible : week ends, got time, practice Civ(PTW) solo or multi whatever. Week time, not so much free long periods rush into a RoN fast solo game "Quick Battle" or try to complete one Age of Conquer the World (campaign mode)