For a reason that we can't understand, an AT&T employee actually responded to Kearney's tweet to correct his math, saying, "actually 1 character in a msg equals abt 1 kb.1024KB=1MB..same conversion to GB-AT&T charges 19.97/mb or 120mb for $30 #fact".
Bad Twitter grammar aside, AT&T's response makes no sense on a number of levels. First, the math is still a little suspect because "1 character in a msg" should not equal 1kb. Also, AT&T forgot to mention that sending that amount of data via SMS is nearly impossible, and completely impractical.
Kearney attempted to take his information to its logical extreme, in calculating that it would cost $35 million to send an HD movie over SMS while roaming on AT&T (which isn't even possible). And, he also went for a more "realistic" angle, by saying that you could theoretically hit that 1GB of data via SMS mark by sending 7.7 million text messages. That's not quite impossible, but if you did send that many texts, we'd suggest you see a therapist rather than bothering AT&T's accounts department.
*this article has been updated