Google is fixing a problem where a Google Logger popup comes up when a user conducts a search on certain browsers.

I am not certain exactly what the logger does but here is a screen shot of the bug. The pop up will come up or be blocked by popup blockers. But when the popup comes up, directly after a search is entered, it looks like this:

The first reports of this came in late June in a Google Web Search Help thread and Kelly from Google has been responding to users, trying to fix it. She said recently:

Some users are saying it is fixed but not all.

Here is a videocast of this in action:

Forum discussion at Google Web Search Help.