Turned the Nexus 7 on for the first time in a while, after updating a ton of apps, I checked the settings for a system update, and sure enough 5.1 was available.
I am anxious to get this update on my Nexus 9 because of the promised performance improvements. It will be interesting to see how well 5.1 performs on the Nexus 7, which has been noticeably slow ever since I upgraded it to Lollipop.
Android Central: What's New in Android 5.1
Well, that's interesting, I just received a notice that Android 5.1.1 update just downloaded. Restart and install in progress. It's a small update, so I am guessing it is a bug fix to Android 5.1.