In the kitchen, always. My parents have always had a rule that we aren't allowed to eat in the bedroom (I still live with my parents) - probably so the bedroom carpet (or other things like electricals) don't get wrecked if a spillage occurs.
In my room, always. I get on great with my flatmates, I'm in third year and we've shared since first, just I think eating is our little private time, after a long day there's nothing better than sitting alone with a big plate of food and catching up on tv
Anyway. I eat in my room, no table in the kitchen; me da broke it in a boxing match that went wrong . So he eats in the sitting room and I eat in my room when I visit him.
At my mum's house, I eat in the living room because I forget it's not my bedroom. No one goes in there but me unless of course it's company. I shut all the curtains to make it dark and just stretch out and cotch, eat, sleep, dance...& everyone's too afraid to interrupt me in there!