Google (Nasdaq: GOOG) is Cuil again. TechCrunch reports that Anna Patterson, founder of the now-defunct search upstart Cuil, has returned to Google as a director.

Previously, Patterson helped shepherd the Google Base directory for cataloguing content to be ranked in its search engine. What role she's taking now isn't entirely clear, but last month she gave a talk at Washington University in St. Louis in which she was identified as Google's "Director of Research." (Kudos to TechCrunch's Alexia Tsotsis for finding that gem.)

Her return is timely. Yahoo! may be laying off hundreds, but Twitter and Facebook are flush and working on ways to capitalize on new social advertising models that could threaten the search king's core business. Groupon has a similar idea that recently set off a $6 billion bidding frenzy in which Google was involved.

And don't forget Bing. Microsoft (Nasdaq: MSFT) this week released a new version of Bing allows users to rank results according to the likes and links shared by friends on Facebook. Mr. Softy has also struck a deal with Open Table (Nasdaq: OPEN) to allow users of the Bing mobile app to make restaurant reservations from within local search results.

With all these innovations, Google's going to need as much help as it can get to keep search users loyal. Patterson can help by offering an outside-in perspective, beginning with the shortcomings that led her and others to create Cuil.

Steak rather than sizzle may be where she'll have the most impact. Cuil earned fame for indexing more than Google but with a far less complex infrastructure. Just 150 servers catalogued the entirety of the Internet and sliced it into areas of specialty to help better predict meaning.

Now that Cuil's gone we know the reality didn't match the vision, but the vision remains compelling to this day. There must be lessons Google can learn from Patterson's experience leading Cuil. With competitors getting more aggressive, now's the time to put them into play.

But that's my take. What do you think? Is Google vulnerable, or a monopolist that needs to be broken apart? Weigh in using the comments box below. You can also rate Google in Motley Fool CAPS.

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