According to cnet's Crave blog, iPhone owners can bypass typing out text messages with a new app:
This is thanks to a new iPhone application that Promptu, a talk-and-type mobile phone application developer, introduced Monday called ShoutOUT. The application is going to be the first voice-to-SMS application for iPhone users in the United States.
The application lets you dictate text messages instead of typing on the iPhone's touch-screen keypad. It also allows for checking the transcribed messages for errors and make corrections if necessary before sending them out to the intended recipients.
Read more @ cnet