Before the official kick off of Google IO 2013, Google Developers site has confirmed the Android 4.3. Not its slighlty lower than confirmed that Android 4.3 is coming and just minutes away from official announcement. Just check out the pic snipped from Google Search Results:
Similarly an hour ago Google Maps new layout gets leaked as Googlers were trying to finalize all the things for it. First they unloaded the new look and than pulled out.