Evan Schuman's StorefrontBacktalk

Google’s stock got slapped around again on Wall Street on Wednesday, after what initially appeared to be an isolated report of a search marketshare drop turned out to be not so isolated. Google shares lost about 1.3 percent of their value.

Google started off the week with a report from Piper Jaffray that that Google Checkout is not winning over a lot of retailers, mostly because those retailers don’t want to surrender that much customer information to Google. This follows a report that Levi.com had officially abandoned Google Checkout.

The initial marketshare report came from ComScore Networks, which reported a roughly one percent month-to-month drop for Google. That report prompted Bear Stearns analyst Robert Peck to send a client note that “We think (the) loss in domestic market share could signal a topping point,” for Google.

On Tuesday, another Internet traffic company called Hitwise released its own figures, which showed a very similar decline for Google. The Hitwise general manager for global research, Bill Tancer, said on his blog that “In fact, the numbers do indicate a slight decline in market share of executed searches for the first three weeks of August,” but he added that he wants to “wait for longer term trends before jumping to conclusions. While 60 percent may represent a saturation point for Google, it also may be a seasonal fluctuation.”

Adding to Google’s woes is a report from MarketWatch that Google is being “pressured by Brazilian authorities for allegedly refusing to turn over information concerning its Orkut social networking feature, which is immensely popular in that country. Brazilian police suspect the network is used to distribute child pornography and hosts groups catering to neo-Nazis.”

Let’s say. Falling stock price, marketshare erosion, unpopular product and then, to top it all off, Neo-Nazis. Yes, I think this is a week that Google would rather not have to relive anytime soon.