Open Radar

 
Summary: The App Store doesn't relaunch apps that it is updating, even though it promises to.

Steps to Reproduce:
1. Install an app. In my case, I have seen this problem with Fantastical.
2. Wait for that app to issue an update. I hope you guys have a way to simulate this, or the bug could take a while to reproduce.
3. Launch the app, so it is running when you click Update. In my case, Fantastical runs in the menu bar, so it is always running.
4. Click Update.
5. At some point during the update process, a dialog appears, telling you that the app needs to be quit to update it, but that it will "be open" after launch. Sorry, I don't have the text of the dialog handy, but I believe "be open" is in there.
6. Click the default button on that dialog - "Update" or "Continue" or whatever it says.

Expected Results:
The app updates, and then relaunches.

Actual Results:
The app updates, but never relaunches. I have to relaunch it manually.

Regression:
This feature was new in Mountain Lion, if I remember correctly, and I'm pretty sure I saw it work correctly in earlier builds, but I can't say for certain which ones.

Notes: I contacted Flexibits, the developer of Fantastical, and they said they have seen this too and that, as far as they can tell, this is an Apple bug.