The changelog for Google Voice doesn't really help too much though, and says that the only update to the app is that it will now have "improved reliability of SMS delivery". That is nice, because there were too many errors sending texts before.
However, Android Police has dug into the APK code and found another addition which will allow other apps to check on Google Voice's configuration settings. It's unclear what functionality this would be used for. Obviously, people want to assume that it has something to do with Babel, but we can't say that for sure.