I also noticed that the AI is quite erratic.
I played two games as Ghandi on Prince - and both times I was WTH pwnd by a single AI. Then I played two games as Alexander on the same difficulty level and maptype (Continents) - and the AI behaved as if it was braindead.
So what happened exactly?
Well, the first game with Ghandi was in fact my very first CIV5 round and I had no strategy whatsoever, I just wanted to tinker a bit. I had three archers and three cities, he had 3 Legions, 2 Horsement and a Catapult. A well deserved defeat.
Then I played as Alexander, just pumped settlers and grabbed as much land with as much luxury ressources as possible. By the time the first Washington DOWed me, I was well ahead techwise and his army was simply vaporized by my fortified (Walls + Castle) frontline city. I left the game around industrial era, because itwas clear that I had won (already triple the points of the second best AI) and I wanted to give Ghandi another try.
This game was brutal. I was corned by an extremly hostile Germany and soon Bismark attacked me. Despite having only few less units than him, I suffered a horrible defeat - he made a brilliant flanking attempt, outmaneuvering my frontline spearmen, crushing 3 archers and a geat general with two Horsemen. After retreating my units, he swarmed and sourrounded my first city, cutting it off and using his archers to destroy it within two turns. Afterwards he waited to get two Catapults and soon I was crushed because he used focused fire on any resistance I brought up against him.
Next game was Alexander again - the AI: braindead. Napolean was about one screen SSE from me. When I had four cities, he still had Paris and nothing more. A few turns later he DOWed me (guess my third city which was next to his capital provoked him) - and with 3 archers, I beat the living hell out of his army of 10 warriors and 3 horsemen. At one point he was just walking left and right in front of my completly undefended city. He did not attack it a single time. So after his men are dead, he offers me peace, including his (meanhwile founded) second city. I accept, because I am curious where that one might be. The area around his capital was incredible fertile - he had rivers, wheat, silk, dye, ivory, marble, gold, silver, gems, but I hadn't seen any french culture with my scouts.
So where was his second city? Yep, about four screens away on another continent in the middle of a desert.
Same with barbarians: Sometimes they just walk back and fourth, leaving undefendet cities alone, ignoring wounded units they could kill, not bothering with any tile improvements. The other time they gang up with three units and burn down the area around my capital to the very last improvment - and while they are already on it, they kill 2 warriors and my only scout.
In conclusion: There is definetly something fishy with the AI.
(j/k), there were some here that voiced their concerns pre-release. Specifically, a lot of people were debating and were excited about the new features (1upt and diplomacy, to be exact) and how that would revolutionize Civ. But some did not look at it from the AI point of view (only from the gamer point of view). If the AI could not handle something as no-brainer as a SoD, how could you expect them to handle something more complex as 1upt? Regarding diplomacy, sure it sounded cool for us to use but there were concerns voiced by some as to how well the AI would use them.
