I got a call from 214-210-0678 on July 15, 2014 at 8:03 pm. I was not home and the caller did not leave a message. My caller ID said, "Texas." I don't know anyone from Texas. My number is on the Do Not Call list and has been for ten years.
If the caller didn't leave a message then by definition they didn't try to sell you goods or services, therefore they didn't violate the Do Not Call list. Calls from non-profits, charities, polls/surveys, political calls and, yes, even calls that hang up without saying anything, are exempt from Do Not Call regulations.