The Economist (great mag but don't read it when you're sleepy) has an interesting article on SMS in the US. Americans only send 7 SMS messages per month compared to the global average of 30 (and as high as 200 in some more savvy parts of the world).
"American telecoms regulations—which encouraged different mobile operators to choose different, incompatible technologies—are also responsible for the dearth of texting. Only last year did the largest American operators agree to pass text messages between their networks—an agreement still only patchily implemented."
[via MarketingFix]
Update: In the UK it looks like the kids are on the other end of the spectrum:
"Getting a phone call or a text message implies an importance - 'someone wants me'. It boosts the receiver's self-esteem and self-worth," explained a spokesman. - Daily Telegraph @ NewMedia Zero