Should I have received an email? Is there a link?
Edit: I guess I missed this:
Edit2: I realized I removed the Feedback Assistant app from my mac when I was having second thoughts about Yosemite Beta. After downloading it again, now I am seeing the available update through Mac App Store. I feel like such a newb.
For anyone else that is hitting a wall like me:
https://appleseed.apple.com/sp/betaprogram/welcome, sign in, follow instructions to download and install Feedback Assistant, launch Mac App Store and check for updates.