• by Laurie Sullivan , Staff Writer @lauriesullivan, May 11, 2010

Wall Street analysts aren't convinced data from comScore's U.S. April 2010 report tell the whole picture of gains in search market share for Yahoo -- up from 16.9% in the prior month, to 17.7%. This marks a continual sequential rise in search engine market share gains for the company that some marketers wrote off long ago.

Analyst don't doubt comScore reported the numbers correctly, but digging a little deeper, some attribute the uptick to various new features that could be falsely raising the numbers. But perhaps comScore and Yahoo should more closely define a search as the industry continues to change.

Broadpoint Amtech analyst Ben Schachter believes the slideshow feature on Yahoo News inflated Yahoo's results. As people scroll through images in the slideshow, they generate a search for each picture. ComScore tracks those searches. Schachter writes that backing out of the queries gives Yahoo about a 16.9% search market share in the U.S., which would make its share flat, compared with March.

Similar to Schachter, Barclays Capital analyst Douglas Anmuth points to Yahoo features -- such as the slideshow -- that recently boosted query numbers counted by comScore. That's regardless of the fact that during the first quarter earnings call with analysts, Yahoo management indicated search share had bottomed and execs expected a rebound in the second quarter.

Anmuth tells us in a research note that April comScore data backs up Yahoo exec's assertions. And while he believes these features boost query numbers, Yahoo has made progress in building search deeper into verticals and providing more search-related links across the site. Anmuth, however, "would prefer to see share gains come more from higher quality searches that could have a greater direct impact on revenue."

Despite the good but cloudy search data, Anmuth likes Yahoo shares based on display strength, margin expansion, Asian assets, and attractive valuation.

J.P. Morgan analyst Imran Khan attributes the increase to a new interface that ties content with relevant searches. He describes the navigation as more likely to occur during a series of searches, which are counted by comScore and contribute to search share. Yahoo also benefited from better data collection at Yahoo Finance, he wrote.

Khan believes "significant user interface changes cloud the picture" that prevents you from comparing the numbers from this month to last. He tells investors not to become too optimistic and explains additional months of data under the new method could help clarify search results.