The buzz in the internet marketing community this week should remind businesses that social media marketing is now key to fueling online leads. From new stats on consumers’ social usage to more reports on the rise of Google+, social took the spotlight, but content marketing and search developments also made headlines.

At the beginning of the week, YouGov released a survey that suggests Google+ will be the second-leading social network within a year. As Brafton reported, Google’s network is expected to cross the 40 million-member mark soon, and it already serves as a valuable channel for content marketing efforts. Nearly half of its 25 million users say they read content on the site daily. Rising Google+ figures were released before it was announced that games are now available on the platform.

The YouGov study suggests that Google+ adoption will negatively impact Facebook, with Google+ users reporting they plan to spend less time on Mark Zuckerberg’s social site. Still, Facebook is trying to remain part of the social (and social marketing) conversation. The company announced a Facebook news feed update that will group articles on users’ homepages according to category. This could be a good way for marketers to insert their branded, relevant posts into social conversations among friends – but users have had a negative response to the update….

Twitter has also made some changes this week. The company is highlighting relevant Tweets with a new Activity Tab. The feature gives users more insight on what their friends are sharing on the site, and this might mean more exposure for branded Tweets, making Twitter an even more appealing social marketing outlet.

Another site that is gaining value as a social content platform is LinkedIn. Following Brafton’s report that the B2B social site has more than 115 million members, new data shows that interactions on LinkedIn are rising. Eighty-one percent of users say they are now part of at least one group, and 52 percent are regularly active in group discussions. This means businesses that contribute branded content to industry conversations can catch users’ interests.

LinkedIn is not the only site garnering more social activity. New data from Pew reveals that Americans are increasingly making social networks part of their online routine. The Pew study indicates that internet users who access social media has surged from 11 percent as of 2005 to 65 percent this year.

No matter the platform, marketers need to get on board with social media. A new survey from just-drinks shows that more than two-thirds of marketers in the food and beverage industry don’t monitor their social ROI. Meanwhile, marketers in the finance industry fail to establish social marketing campaigns at all. Just 15 percent of finance marketers utilize Facebook for marketing, and only 8 percent use Twitter. As Brafton has reported, they are missing social content leads… and social marketing may be driving a lot of leads among mom and dad shoppers this season.

A new survey shows that social media will play a big role in back-to-school shopping. Thirty-five percent of parents intend to look for social media as they shop. Mobile will also be key to back-to-school purchases as 64 percent of parents say they will rely on their smartphones to find deals this season.

Mobile marketing is proving its worth in lead generation. Smartphones are becoming integral to consumers’ shopping habits, according to a recent report from Experian Simmons. Fifteen percent of on-the-go shoppers use their phones and tablets to inform timely purchase decisions. With this in mind, it’s no wonder that experts agree mobile websites are a must. Plus, as Brafton reported, some businesses are seeing a surge in local conversions from mobile site visitors, indicating mobile search opportunities can’t be ignored.

Speaking of search, the latest search engine rankings reports from Hitwise and comScore were released this week. ComScore says that Google’s share has remained steady, while Hitwise indicates that the search giant lost 2 percent market share in July. Meanwhile, both firms suggest Bing-powered search made modest month-over-month gains, with Yahoo searches fueling growth.

Yahoo also made the news this week for its updated image search. As Brafton reported, the new search makes it easier for users to see optimized visual content, and marketers who offer visuals on their sites should make note. Search Engine Roundtable reports that Google also released a new image search algorithm which credits the original sources.

Some marketers thought they were seeing other algo updates from the search giant this week, with rumors of Panda 2.4 flying. However, Google told Search Engine Land that “no Panda update is currently occurring.”

Marketers who want to stay on top of Google’s updates can check out SEOmoz’s Google Algorithm Change History document that was released this week.

Also, businesses can expect more search insight from Google directly as it was announced this week that Matt Cutts’ webmaster tutorials are getting a facelift. Google explains that the new format features “longer videos which cover important webmaster-related topics” instead of the quick SEO Q&A style videos that have been the hallmark of the Webmaster Central channel on YouTube.

One piece of SEO advice Cutts has repeatedly offered marketers is that they should focus on content, and his sentiment was supported by new data indicating that content fuels search success. As Brafton reported, MarketingSherpa’s 2012 Search Marketing Benchmark report reveals that content marketing is cited as a top SEO tactic.

Content is proving especially valuable for B2B firms, with a new ebook indicating that it has improved search rankings for a number of businesses. Moreover, some companies have seen up to 191 percent increases in organic traffic, and others report as much as 70 percent of new business is generated via blogs.

There are also new content aggregation channels that can increase branded content’s visibility. Google News has launched its Editors’ Picks RSS to promote top, branded News content, and Digg just announced its Newswire, which will promote popular breaking news stories.

Next week, marketers should stay tuned for more updates about Google+, Facebook and other social sites. Plus, we can expect a lot of headlines surrounding SES San Francisco as marketing experts convene to discuss the latest developments in search. (Brafton will be live reporting!) Stay tuned.