The screenshot was of Mozilla Firefox.
The image inline above is a larger version of the screenshot, available from the original AP article but not available from seattlepi.com. But if you look at this crap all day long like I do, you can even see it in the teeny-tiny version - the Mozilla dinosaur is clearly present in one of the tabs (!) showing on the tab bar(!), and even without resorting to that, you can see that in the screenshot, the "back" icon is a green arrow in a white circle, whereas in IE6, the "back" icon is a white arrow in a solid green circle.
Microsoft's PR firm's take on this was predictable:
Brian Peterson, of Microsoft's PR firm Waggener Edstrom, said: "None of our approved/distributed screen shots of MSN Search were made using a Mozilla Firefox browser. Moving forward, we will not be commenting on this issue".Uh huh. Sure thing, Mr. Peterson... you "did not have sexual relations with that browser... miss Firefox." Gotcha.