Yesterday afternoon at about 4pm (EST), the Google AdWords magnifying glass feature went missing. The magnifying glass is a little icon you can find in the keyword list within your AdWords management interface. When you mouse over the icon, up comes information regarding your quality square factors. Here is a screen capture:

That feature went missing around 4pm (EST) yesterday and finally came back around five hours later.

In a WebmasterWorld thread, AdWordsAdvisor confirmed the issue at 7:48 pm and then about an hour later informed us the issue should have been resolved.

I can confirm that I see the magnifying glass this morning.

Forum discussion at WebmasterWorld.