US teens text ten times an hour

"Nielsen analyzes more than 40,000 mobile bills every month to determine what consumers actually are spending their money on. The results are staggering: American teenagers are using 3,146 messages a month, which translates into more than 10 messages every hour of the month that they are not sleeping or in school. Even the under 12 segment are sending 1,146 messages per month, which is almost four text messages per waking hour that they are not at school.
While the 13-17 year old age bracket is already highly saturated, the last holiday season was good to the under 12 segment when it came to text messaging. A full 8 percent increase in SMS usage was measured combined with a near doubling in text message volume for that segment in the following quarter (Christmas, Hanukkah, and Kwanzaa are late in December, so usage increases will be recorded in Q1)."
Source: Research by Nielsen, reported on their blog, 27th January 2010