The text to speech is slow and it is a drab. I can open up Wikipedia and run through the content 5 times faster than that. You will have lot of impatient users waiting for the information they actually want. It is like calling your bank up and listening to their long IVR menu when actually you want to report your stolen credit card.
Imagine waking up every day to the same drab slow dull voice that tells you about the day's weather.. !!