“The act of texting automatically removes 10 I.Q. points,” said Paul Saffo, a technology trend forecaster in Silicon Valley. “The truth of the matter is there are hobbies that are incompatible. You don’t want to do mushroom-hunting and bird-watching at the same time, and it is the same with texting and other activities. We have all seen people walk into parking meters or walk into traffic and seem startled by oncoming cars.”
Source: http://www.nytimes.com/2008/09/20/us/20messaging.html?_r=1&oref=slogin
That is the reason why the iPhone does not allow for sms forwarding etc... texting reduces your I.Q., We wouldn't want to lower your I.Q. that much that you would go and buy a Blackberry ;-)