BA has made great improvement in this area, particularly on the 777s. Most flights in the past 6 months that I've been on have been set to a very comfortable temperature, and the past problems of being too hot (most of the time) are gone. Out of my last 20 flights on BA I can't recall any that had a temperature problem (while in 2002 about 90% were too hot). AA also operates 777s and always had a comfortable temperature, so this seemed to be a BA specific problem.