Wil Wheaton AKA the guy on Star Wars recorded himself reading from his own book and then recorded the Kindle 2 reading the same passage. The result, as you’ll hear on his blog, is inconclusive (what if TTS gets so good it will sound JUST LIKE WIL WHEATON? WHAT THEN?) but it kind of shows where everyone’s head is at in terms of the Authors Guild.
Again, rights are great and I want money for my writing. Everyone is on the same page here. But there are more pressing matters at hand namely how to sell content sanely and without selling your soul, as Cory D puts it. Everyone wants to make a buck but why fight the inevitable.