here is the .blend file
i made it in blender 2.25, so i’m not sure how it runs in other versions
hopefully this can answer most of your questions
the physics is just a round sphere boucing around in and enclosed box/container (frictionless) much like air hockey, birds eye view
the AI is very basic, and yes, when there is more than 1 ball on the field it kinda screws things up with the AI. by using large invisible meshs, when the ball is detected above the paddle, the paddle moves up and when the ball is detected below the paddle, the paddle moves down… having AI keep track of numerous balls and knowing which ones it can get in time sounds like a bit too much work for me to bother with. not too great with python.
i think many games today have forgot about fun gameplay, they look great, but they’re hard and just drag on, sometimes turn into more of a chore rather than a game, hopefully we’ll see alot of new exciting stuff with X360 and PS3