The FCC reverses its former position on EAS text-to-speech, permitting stations to begin using it today (May 7, 2012). The FCC’s main issue with Text To Speech (TTS) was that it may not render the text accurate enough to be understood, especially in emergencies. This can lead to confusing messages and defeat the purpose of EAS altogether.
I have played around with some text-to-speech software and indeed it can mangle words, mispronounce punctuation as a part of the sentence structure, mumble, etc. Further, as I have said before, listening to some robo voice is very impersonal. But, I suppose that is the point, isn’t it; some big government agency computers generate messages that no one person is really responsible for. Bureaucratic paradise.