Here's Brafton's take on the top internet marketing news for the week ending March 25.

Twitter marked its fifth birthday this week, and subsequent chatter about its milestones took over online marketing conversations. Along with search marketing updates from SES New York, the microblogging site was one of the leading internet marketing topics discussed on the web for the week ending March 25.

With Twitter's fifth anniversary came a report from Edison Research indicating that it has reached nearly universal awareness among online consumers, with Brafton reporting that 92 percent of Americans over the age of 12 are familiar with the microblogging site. Additionally, Twitter announced several milestones – including data on its rapidly growing user base.

The good times are expected to keep getting better for Twitter, with eMarketer predicting that more than 20 million Americans will tweet in 2011. By 2013, the number of users is expected to exceed 27 million – a far cry from Facebook's 500 million users, but a significant audience for marketers nonetheless.

Another social site hitting new heights in terms of users is LinkedIn. The professional network announced this week that it now boasts 100 million members, and as Brafton reported, it adds 1 million new members each week.

LinkedIn may also be increasing its appeal to B2B social users with the recent launch of its news aggregator platformLinkedIn Today. The service offers top news headlines to users according to what is happening in their industries (based on which stories are generating the most public shares, as determined by Twitter). The tool is a good way for marketers to stay on top of industry developments and discover what other people in their professional networks are reading.

Twitter data is also now a part of Bing News. As Brafton reported, Microsoft's News search service now offers a public updates feature, which gives users Twitter results related to News queries. The tool could be good for content marketers who distribute and encourage sharing of their articles via Twitter, as it helps put brands in conversation with industry news developments.

Bing also generated headlines this week for new Bing for Mobile search services. As Brafton reported, Microsoft has updated Bing for Mobile to include easier image search navigation, transit directions and a reorganized shopping search experience. With the updates, the company hopes to improve its mobile web browser, and – perhaps – shift the mobile search market by taking some of Google's share.

On the subject of mobile market shifts, AT&T announced plans to acquire T-Mobile this weekend. The merger would put AT&T well ahead of Verizon in terms of subscribers, and mobile marketers may want to look for ways to engage an “AT&T-Mobile” audience if U.S. regulators approve of the deal.

Internet marketers might want to be on the lookout for mobile marketing opportunities in general. As Brafton reported, data collected by eMarketer suggests mobile shopping – and mobile purchases – are on the rise. It seems that smartphone subscribers are particularly interested in using mobile search to find nearby businesses, so local content marketing may be a good way to engage and attract consumers in a communities.

News from the week indicates that brands may also find relevant mobile audiences among tablet users. As Brafton reported, tablet users are rapidly growing in number, and they cite media content and improved mobile internet access as top reasons for making purchases.

Content marketing could be key to converting mobile and traditional online searchers. A report from this week's Custom Content Conference indicates that custom content increases purchase likelihood. CMOs are increasingly seeing the benefits of custom content marketing, with more than one-third saying it is the future of marketing. Plus, 61 percent of consumers are more likely to do business with brands that offer custom content.

In addition to winning over online consumers, quality content is necessary for ranking on Google in light of the recent Panda update. Experts at SES NY spoke about the update in depth, as State of Search reports.

SES attendees were also interested in the future of search, citing social and local developments as important to the market. As Brafton reported, experts in attendance seemed to agree that “it's all about local.” This conclusion supports news about skyrocketing revenue from daily deal finders that target local audiences, indicating local marketing is a must.

Still, SES pros remind marketers that the social search realm is still developing, and they encourage brands to “go local-social.”

It seems that Google chose to go social this week, as the company that is increasingly known for its forays into the local market is rumored to be adding a new social layer to its search. As Brafton reported, some users have reportedly been asked to connect to Twitter while they search to see which results “friends are talking about.”

Another search development from Google is this week's release of Page Speed for Chrome. This tool is good for SEO, as it helps developers make their sites faster on Google's browser.

The search giant also generated murmurs over its strange relationship with BeatThatQuote. As Search Engine Land reports, Google acquired this company and then punished it in the rankings for bad web practices. BeatThatQuote's penalties were lifted in what some say was a suspiciously short amount of time. Then (following media coverage) the search giant penalized the site again, claiming it noticed more bad practices. Scandalous?

In spite of this ordeal, Google seems to be doing fine in terms of consumer reputation – it was named by Brand Finance as the top brand of 2011. Also making the list (for the first time) was Facebook, which speaks to the rising tensions between the search giant and the social behemoth.

As Brafton reported, analysis from Citi suggests Facebook is gaining ground in driving traffic to websites. While Google remains the leading traffic driver, the report demonstrates the value of social marketing and Facebook's rise as an online property.

Facebook came out with some new features this week that further position it as a top marketing platform. It is testing real-time ads that put consumer relevancy first, and it also updated Facebook Questions so that is easier for users to recommend brands in their community answers.

Speaking of answers, Yahoo launched a new search feature this week that gives users direct answers to their queries when possible. Similar to Google Instant, Yahoo's Search Direct predicts queries and offers top results or answers in a drop-down box while users type.

Search marketers should take note of this and other developments as they plan their campaigns in order to try to get an edge. In fact, as Brafton reported, many SMB search marketers need all the help they can get in attaining an edge – many small businesses say they need assistance to maximize search marketing campaigns.

Looking ahead to next week, internet marketers might expect to hear more on the mobile marketing front in light of this week's T-Mobile shake-up. Also, we can expect continued headlines from this week's SES conference. Stay tuned!

Katherine Griwert is Brafton's Marketing Director. She's practiced content marketing, SEO and social marketing for over five years, and her enthusiasm for new media has even deeper roots. Katherine holds a degree in American Studies from Boston College, and her writing is featured in a number of web publications.