The Seattle Post-Intelligencer is reporting that, next week, European Union regulators will approve Google's acquisition of Web advertising firm DoubleClick for $3.1 billion. When Google made the offer almost a year ago, much was made of Microsoft's perceived mistake in not beating Google to the purchase. While the deal has been pending, Microsoft has moved forward with a purchase of aQuantive and put an offer for Yahoo on the table.

Now, a new question is whether approval for finalizing of the Google/DoubleClick deal will damage Microsoft's potential in the online advertising market even more than expected a year ago. Google has already helpfully pointed out areas for antitrust scrutiny in a Microsoft-Yahoo merger, including the IM market. In doing so, it seems to indicate that it wouldn't attempt to outbid Microsoft for Yahoo, a possibility some have considered.

Ballmer said this week at his company's MIX08 online technology conference that in the event that the Yahoo acquisition goes through, the two companies would naturally eliminate many areas of overlap, but the main goal is to capture online advertising and search market share from Google. But it seems that Google's $3.1 billion purchase may put in mortal danger Microsoft's already shaky, 10-times-the-size bid for Yahoo.