Apple Looking Into Text-to-Speech Converter for the iPhone

Apple has filed a patent application for a system that could convert text to speech and vice versa on the iPhone, Patently Apple reports.
The proposed system would be helpful in noisy environments, as well as situations where the user cannot talk out loud, for example at a meeting. Apple’s solution for the first problem would include noise detection in the handset; when the outside noise is too loud, the phone would automatically convert the speech from the other end into text. And if a user is at a meeting, he or she would be able to type in text, which would be converted to speech and sent to the party on the other end.
Also, in a situation where text messaging is needed but for some reason, the system could be activated on both ends, with both speakers talking into the handset and their words being converted to text and sent to the other party.
Would this feature be useful to you? Can you think of any other ways in which text-to-speech conversion and vice versa could be used? Please, share your opinions in the comments.