"Switch your phone off?" How quaint. 
It was quite interesting when I watched Cabin in the Woods yesterday. There were only about 15 people there, I normally only see blockbusters here, and this was a relatively obscure film, I had to drive an extra 20 minutes to get to the cinema that was showing it.
This was a dedicated cinema fan crowd and everyone behaved impeccably. No chat, no texting, no phone calls, no munching on load snacks. The great news is they have eased up on the censorship here. They used to have zero swearing (which they just mute out) and no nudity or sex but when I heard the f-word in X-Men First Class I dared to try an 18 rated film (18 rated here at least). There was a small cut in the sex scene in the woods that was obvious but I think they left the rest intact.