The biggest takeaway from the U.S. DOJ (and the EU) approving the Microsoft-Yahoo search partnership without any restrictions is that the Varney DOJ Antitrust Division implicitly agrees with the Barnett DOJ Antitrust Division (which blocked the Google-Yahoo Ad Agreement) -- that Google is indeed an dominant and enduring search advertising monopoly.
If the DOJ did not believe Google was a monopoly, traditional antitrust analysis would have had more serious problems with the #2 and #3 competitors in a highly concentrated market combining forces.
This is a negative precursor for Google generally -- that they are indeed the next big antitrust problem of this decade.
It is also a negative precursor for the:
- FTC's antitrust review of Google-AdMob; and
- DOJ's review of the Google Book Settlement.
Google, you have a problem.