What was your favorite Google I/O keynote announcement?

The announcement section is over, and all that's left of the Google I/O 2013 keynote is a question and answer section with Google CEO Larry Page. There have been a ton of announcements across all of Google's products from Android to the web to iOS and more. So, the real question is: What was your favorite Google I/O keynote announcement?
If you need a refresher on all of the announcements, there were: new APIs for location tracking, Android Studio, Google Play Games Services, Samsung Galaxy S4 with stock Android, Google Play Music All Access, new WebM and WebP formats, new one-tap Checkout button, Google Play Education, Google Hangouts integrated messaging app, Google+ UI and Photo updates, voice search and Google Now improvements, and Google Maps updates.
Let us know in the poll, and in the comments!

Follow us on Google News
Things that are NOT allowed:
To help keep our community safe and free from spam, we apply temporary limits to newly created accounts: