There were a lot of great announcements last year's Google I/O. But three things stood out to me.
First it was the great improvements they did in Google Play Game Services. Specifically that it is
cross-platform with cloud saving, achievements and multiplayer. As soon as I heard that Google released the new Google Play Music with the option of a subscription service at $9.99/mo (discounted at the time at $7.99) and a 30 day trial, I signed up! I think this was a great deal and forces other similar services to compete and improve their own services. Another API and service I was excited about (even though most ppl did not care for it) was the changes they made for Google Cloud Messaging. It supported persistent connections, upstream messaging, and notification sync. I hope this year is as big and as awesome as last year's Google I/O. Oh yeah and there was that Glass announcement...