Marketers keeping track of winners and losers from changes in Google's spam algorithm might want to know that this week Matt Cutts announced changes. Cutts said the change better identifies Web sites using aggressive Web spam tactics against Google's quality guidelines. He emphasized the importance of White Hat SEO, and said the change should influence about 3.1% of English Google queries.

Search engine marketers have been hearing a lot about over-optimizing penalties lately. Sujan Patel tells us how to check for the many contributors to a drop in search engine ranking. He offers up some suggestions for fixing the problem. For example, if the ranking fell on Google, start with checking in to Google Webmaster Tools. Look for recent updates on SEO news sites, and determine the extent of the penalty before diving in to try and fix it.

People search engine start-up Ark.com has raised a $4.2 million seed round. Among the investors are Andreessen Horowitz, Charles River Ventures, Greylock Partners, Intel Capital, SV Angel, Atlas Ventures, Crosslink Capital, Expansion Venture Capital, Felicis Ventures, Lightbank, Salesforce, Tencent, Transmedia Capital and several angel investors, according to Liz Gannes. She tells us that more than 250,000 people have signed up for Ark beta invites.

Local search advocate Jeff Beard serves up tips on mobile and desktop local search listings, and how to keep consumers' trust in the information found in listings on the Web. He tells us these listings now act like anchors to identify and pull in important information like Web site URLs, reviews, photos, coupons and hours of operation. The 2012 Localeze/15miles Local Search Usage Study from comScore reveals 61% of survey particpants said when searching for local business information, local search results are the most relevant.

Google began selling unlocked Galaxy Nexus smartphones directly to consumers through its Google Play online store. It's been two years since the Mountain View, Calif. company tried to sell the Nexus One online. Some might consider the first go-around less than perfect. Since then, Google has increased its phone-based customer support, according to Amir Efrati.

What's important in the data marketers use? Some C-Level executives don't understand the value of metrics in campaigns and the consequences of choosing metric x over metric y as key performance indicators (KPIs). Avinash Kaushik provides insight on how to choose metrics, consider page views vs. loyality, revenue vs. economic value, number of followers vs. fans, and more.

Jeff Allen serves up some tips on optimizing paid-search campaigns, telling us that the "sneaky profit killer keywords" spend money and get conversions, but hide beneath well-performing ads. Allen explains that there are many other metrics that dig below the surface, but for now he focuses on the value of ads per visit -- "revenue generated / clicks = PVV."

Eric Schmidt and Larry Page, along with Microsoft's former Chief Software Architect Charles Simonyi, Perot Group Chairman Ross Perot Jr., and movie director James Cameron have invested in a startup focused on natural resources and space exploration. The company plans to mine natural resources from asteroids. David Angotti points to Michio Kaku, a physics professor at the City University of New York, who believes entrepreneurs and privatization could possibly accomplish what the government cannot.

Improving the visibility of a Web page isn't easy, but when done correctly it can pay off. Marketers stuck in a tough spot and confused about whether to optimize or walk away from a project might want to check out the latest stats compiled by Eric Siu. If nothing else, statistics like "79% of search engine users say they always/frequently click on the natural search results" could provide valuable insight into the next optimization project -- or a little incentive to work smarter as well as harder.

Rand Fishkin tells us about changes that marketers should make to SEO practices to avoid over-optimization Web site penalties from Google. He provides examples and suggests that marketers ensure the title tags are authentic and read as if a human wrote them. He also advises that links should be logical and useful rather than manipulative and repetitive. Fishkin provides numerous tips to prevent over-optimizing a site.