A few additional bugs (in addition to earlier ones I posted regarding maintenance and slavery) I noticed during current game (beta 5)
1) I think AI trading of money/techs for per turn resources needs to be fixed. First, they offer ludicrous amounts of money/techs for only 10 turns of a resource. Also, when it is the computer trading away the per turn resource, it never actually cancels it after 10 turns (like the human player will). I have an AI giving my gold per turn so far FOREVER even though he could have cancelled long ago (he is getting absolutely nothing in return)
2) Is fixed borders actually working? I was near a neighbor and we both had monarchy with fixed borders, but my culture spread over his border and ended up flipping a tile.
3) This is a minor bug but thought it was interesting. When you have a cottage that you aren't working, forest and jungle can actually overgrow it, which then allows the tile to have both a cottage and forest/jungle. Then when you start working the tile you get both the cottage/hamlet/etc benefit plus the extra hammer for the forest...