A while back there was a rumor floating around that Valve wanted apple to pay them up front cash to port any of their games to the apple platform.
EA hasn't been serious about creating good ports for their games either.
Cider works as a technology -- but they for some reason thought the technology was in, and it was in fact, still needing to be worked on, thats why they delayed and released products that don't work.
Aspyr probably has the best record for porting games, but even some of theirs don't run as well as they should... meh.