The compendium of physical activities! If it's hosted on google it must be true?
This has an obvious "error" (golf walking - pulling clubs is more strenuous than golf walking - carrying clubs?) but it is interesting nonetheless.
In the beating a dead horse category - it lists golf as a sport and skiing as a winter activity.
Skiing ranges from 4.3 (light) to 8 (racing) METs, but is qualified by "active time only" (presumably excluding lift time). Golf ranges from 3.0 (driving range) to 5.3 (walking and pull cart).
And finally ... there is now proof that golf is better than sex (at least by METs)!