>>Is far as no learning curve, that will be a bit of hyperbole since it is different from normal texting or a full qwerty keyboard.
Well, maybe an exaggeration, but it has the same learning curve insofar as using a QWERTY thumb board for the first time, compared to the learning curve of doing T9 for the first time.
i.e. Much, much, much shorter than T9 :D Essentially, nearly no learning curve differential between using a QWERTY thumbboard for the first time versus this format for the first time. (relative to the learning curve of T9)