How to unplug from thunderbolt display in a safe way?
Jettison from the App Store for $1.99 has helped me with this.

It's a menubar application that helps in 2 ways: You can click and eject all drives (the only problem is that you can't say something like "Only eject drives connected to the Thunderbolt Display"); you can also select an option to eject all drives when putting the computer to sleep (so if you are disconnecting your computer to go somewhere, you can put it to sleep, wait a moment, then unplug everything).

That being said, I now use Launchbar to accomplish this. I just activate Launchbar and select "Eject All Ejectable Volumes". I'm willing to bet other app launchers (Quicksilver, Alfred) can do this just as easily.