All eyes are on Google as a report says that they are the ones responsible for tipping off the EU that Microsoft's Windows 7 no longer gave a choice of browser after Service Pack 1. Google, in conjunction with Opera, are said to be the responsible parties for causing the investigation that led to Microsoft being fined $730+ million.
Of course Google and Opera had lots to gain by Microsoft being forced to promote their browsers. What company wouldn't want their product being promoted when a competitor's product was installed? Furthermore, Google and Microsoft haven't been on the best of terms as of late. Looking at Microsoft's Gmail smear campaign, one doesn't have to wonder why.