With this new release Google is saving us the effort of skulking around and/or waiting for an official update that might never come. This will come as great news for many people using their smartphone as a hands-free reader, a group that includes more than just the visually impaired but also anyone who needs to keep their hands free for other activities.
TBH this won't affect me much; I much prefer the Ivona voices. They're much more realistic than the stock voice supplied by Google. I also tend to use the Kindle Fire HD more, and it ships with them as stock.