This is one of things some Google users were surprised to discover on Monday, when Google launched its new "My Account" feature. The company is trying to give users a better idea -- and more control -- over what information it collects. >:(
http://money.cnn.com/2015/06/02/technology/android-voice-dictation/index.html
You've been able to access this for a while. Probably since voice search was introduced. I think they just moved it. I previously used it to see what my kids had searched for!