I see this objection often. It's the "safe" objection to any strategy game.
In the end you're playing a computer; it's going to be predictable at some point. You're going to eventually figure out any flaws or how to decisions are ranked and exploit it. You're not playing chess vs. deep blue where you must be Kasparov to have a chance; and Civ is more complex than Chess.
So I guess what I am saying is this:
I think people's expectations for the AI become too high because it's a moving bar (or they're unrealistic to begin with). Once you figure out a weakness, you exploit it and then become upset that the AI is not able to adjust. Civ has ALWAYS compensated with that by granting unfair buffs to the AI opponents; it must to it: every strategy for every scenario cannot be programmed and accounted for without completely trashing the speed of the game (and therefore play-ability - not many would wait for an end of turn where every possibility is mapped out X turns in advance like and advanced AI would need to do). There is a balance to be struck and buffs to the AI smooth it over.
In the end you're left with is it fun? These things added in this expansion look fun, and I can't wait to try them out