Well, I played some more, and I'm unhappy with the AIs. Totally war-centric, and apparently only hostile towards the players, so, all AIs against the human. I guess you could circumvent this by playing against humans only per wifi, but Civ Rev is something I'd play when I'm not around my computer (and router), so good AIs would be helpful. I'm probably spoiled by the Civ4 AIs, though. For a DS game it's still well done, but there are precious few DS games that I really enjoyed (AW, Anno, Clubhouse Games, Puzzle Quest, FF3).
It's better than nothing, but for mobile Civ it may be better to buy one of those sub-laptops (Acer Aspire One for example) and put Civ 1-3 on it. Sure, larger than a DS, and twice as expensive, but still fairly small and light (less than two pounds / one kg).