elprofesor
Pluri-editing poster
That's a bit harsh 
They obviously don't take into consideration the fact that you are human, and thus will win a war even with slightly worse military strength, or completely annihilate their army, given a chokepoint and a citadel. Other than that, they would usually have good odds of winning if their tactics were as good as that of a human.
There's also the thing that they sometimes declare war on you because they hate you infinitely, or because they know they have lost. That's a different (and recurrent) subject, that I personally find reasonable, not a problem per se (although obviously a nuisance).
I just find that the AI doesn't understand protection pacts at all.
--------------------------------------------------------------------------------------------------------------------------------------
Another problem with protection pacts: it expires as soon as one DOW has been done. Which may seem like a good idea, but isn't when 2 civs declare war the same turn, and your partner only declares war on the feeble one.
And about how they miscalculate PPs: if civ A won't declare on civ B (and viceversa) because their military power is too close to each other, and you are a puny cultural civ (just tested), go see your best buddy among them, sign a PP (easy if you yourself have never been denounced, etc), and piss the other one (don't settle near me! gimme that! and I denounce you!), he will DOW you (you are a puny cultural civ, remember? he probably covets your lands, and doesn't care about you holding your breath).
On a side note, if have just seen England settle a city within 3 tiles of another in an archipelago map (should be impossible...?).
I also had a minor minimap problem in two games: the cities of some civs didn't appear, only their cultural borders. It has only happened for standard games (I own a laptop, so I try to play smaller games), and fixed itself after reloading.
On a completely aside note, it would be "really cool" if we could access the civilopedia from the main menu. I guess it has been asked before, but seriously, wouldn't that be awesome? (sorry for the thinly veiled critic, but it really bothers me that I have to load the game AND a game to check it; especially when I want to recheck the special abilities of some UU before chosing a leader: why isn't there their info summary, like during the leader loading screen?)
And a last note: barbarian ships seem to ignore improved sea spots post-patch, which renders them next to harmless (you can't work tiles within 2 hexes of them, but still...)
PS: sorry for my parentheses addiction.

They obviously don't take into consideration the fact that you are human, and thus will win a war even with slightly worse military strength, or completely annihilate their army, given a chokepoint and a citadel. Other than that, they would usually have good odds of winning if their tactics were as good as that of a human.
There's also the thing that they sometimes declare war on you because they hate you infinitely, or because they know they have lost. That's a different (and recurrent) subject, that I personally find reasonable, not a problem per se (although obviously a nuisance).
I just find that the AI doesn't understand protection pacts at all.
--------------------------------------------------------------------------------------------------------------------------------------
Another problem with protection pacts: it expires as soon as one DOW has been done. Which may seem like a good idea, but isn't when 2 civs declare war the same turn, and your partner only declares war on the feeble one.
And about how they miscalculate PPs: if civ A won't declare on civ B (and viceversa) because their military power is too close to each other, and you are a puny cultural civ (just tested), go see your best buddy among them, sign a PP (easy if you yourself have never been denounced, etc), and piss the other one (don't settle near me! gimme that! and I denounce you!), he will DOW you (you are a puny cultural civ, remember? he probably covets your lands, and doesn't care about you holding your breath).
On a side note, if have just seen England settle a city within 3 tiles of another in an archipelago map (should be impossible...?).
I also had a minor minimap problem in two games: the cities of some civs didn't appear, only their cultural borders. It has only happened for standard games (I own a laptop, so I try to play smaller games), and fixed itself after reloading.
On a completely aside note, it would be "really cool" if we could access the civilopedia from the main menu. I guess it has been asked before, but seriously, wouldn't that be awesome? (sorry for the thinly veiled critic, but it really bothers me that I have to load the game AND a game to check it; especially when I want to recheck the special abilities of some UU before chosing a leader: why isn't there their info summary, like during the leader loading screen?)
And a last note: barbarian ships seem to ignore improved sea spots post-patch, which renders them next to harmless (you can't work tiles within 2 hexes of them, but still...)
PS: sorry for my parentheses addiction.