I love farming. More specifically, I love herbalism -- and even more specifically, I love gathering herbs in Zangarmarsh. You'll know you share a realm with one of my herbalists when you see those herbs up on the AH on a regular basis. Zangarmarsh is a serene, evocative zone with a predictable herb circuit. I can chat in guildchat with my WoW guild, on TeamSpeak with my other gaming buddies, and keep Facebook, Twitter, or Google Reader up on the other monitor. The total experience isn't the same without all the elements, but it never fails to satisfy after a deadline-driven day.
On the other hand, I'm put off by players who let slip that they're watching a movie while they're tanking my group or eating pizza during a raid. These are the activities I do for the challenge, to explore the limits of the story, the setting, the gameplay. Being fully immersed and fully engaged is what makes them fun; when they stop being immersive or engaging, I stop running that content (unless I'm playing with a group of friends strictly for kicks and giggles).
Different strokes for different folks -- sure, I get that. But this is one common player habit that stumps me. If you do enjoy doing something that calls for significant attention while you're grouping or raiding, 'splain this: Wouldn't you enjoy each activity more if you gave it your full attention?