By 2013, social network advertising revenues will reach $10 billion worldwide, up from $5.54 billion this year, according to eMarketer. Facebook is set to grab the lion’s share of those revenues, with Facebook’s ad sales expected to climb from $3.8 billion this year to $7 billion in 2013 (70 percent of the total).

Twitter’s ad sales are expected to rise from $139.5 million in 2011 to $399.5 million in 2013. LinkedIn will also see impressive ad revenue gains. eMarketer expects LinkedIn’s ad sales to grow from $140.8 million this year to $249.6 million in 2013.

If the conversion rates of telecommunications marketers are any indication, mobile ads are about 600 percent more effective than standard banner ads.

Research by MediaMind shows that, among telecommunications marketers at least, the conversion rate for mobile ads is six times or 600 percent the performance of standard website banner ads.

In a sign that online advertising has truly gone mainstream, eMarketer estimates that retail and consumer packaged goods (CPG) will account for the biggest share of new U.S. online advertising spending in 2011.

Overall, the research firm forecasts online advertising to grow by 20.2 percent to reach $31.3 billion this year. Retail already accounts for the biggest share of online advertising and is expected to grow by 24 percent to reach $6.78 billion. The CPG industry will grow by 14 percent to reach $2.46 million in total online ad spending.

U.S. based Consumer Watchdog has asked the U.S. Federal Trade Commission to investigate eight (8) online advertising companies for violating their privacy policies regarding online tracking. Furthermore, according to Consumer Watchdog, the companies’ deceptive behavior means that self-regulation of online privacy and behavioral advertising isn’t working.

According to Consumer Watchdog, the companies – 24/7 Real Media, Adconion, AudienceScience, Netmining, Undertone, Vibrant Media, Wall Street on Demand and TARGUSinfo Advisor – are all members of the self-regulatory Network Advertising Initiative (NAI). Yet, based on a recent study, all violated their stated policy of not tracking consumers who opt out of receiving ads based on their online activity.

176 million U.S. Internet users watched online video content in May 2011 for an average of 15.9 hours per viewer, according to the comScore Video Metrix service.

The more than 8 out of 10 U.S. Internet users (83.3 percent) who watched online video, mostly did so on Google Sites (mainly YouTube.com), which attracted 147.2 million unique viewers during the month.

According to Ryan Beldham, founder of MyWebRevolution.com, Google is a monopoly. In this interview, I asked Ryan why he thinks Google is a monopoly and what he thinks should be done about it. As a libertarian and fan of free markets I still think people are free to do business with Google or go elsewhere. What about you? Do you agree with Ryan? Share your thoughts in the Comments.

Anna: Why do you consider Google to be a monopoly?

Ryan: This is not an easy question to answer and is really the basis of my entire argument. But to try and sum it up, you must first know how to define a monopoly. I define it as a product or service that has exclusive control in its market space, and, must control the prices set in that market. It is important to note that this is a two-fold definition and gives a set of criteria for determining what a monopoly is.

Where do U.S. hotels, bed and breakfasts (B & Bs) and innkeepers spend most of their marketing budgets these days? If you’re involved in the travel industry – or have recently researched or booked travel – you’ll know the answer: on the Internet!

Of the three biggest marketing expenses among accommodation businesses, the biggest expense is online advertising and the third is online travel agency commissions.

Hotel brand managers should impose stricter terms on their affiliates and channel partners, who, according to MarkMonitor, are ‘brandjacking’ hotels to the tune of $1.9 billion in lost annual online bookings.

Based on recent research conducted by the firm, MarkMonitor reckons affiliates – particularly hotel aggregators – are effectively ‘brandjacking’ hotels by bidding on hotel brand terms in the search engines. According to MarkMonitor’s research, affiliates are costing the hotel industry around $1.9 billion in lost annual online bookings.

BIA/Kelsey estimates that total U.S. mobile ad spending will grow from $790 million in 2010 to $4 billion in 2015.

In particular, the local portion of that total will rise from $404 million to $2.8 billion, growing from 51 percent of overall U.S. mobile ad spending to 70 percent by 2015.

Facebook’s display advertising revenues will grow by 80.9 percent to reach $2.19 billion in 2011, according to eMarketer. This will see it surpass Yahoo! as the leading display ad sales company in the U.S.

The rise in Facebook’s display ad revenues actually reflects a slowdown in growth, considering Facebook experienced triple-digit display ad revenue growth in 2009 and 2010 when its display revenues were at relatively low levels. eMarketer expects growth to slow further to 31.3 percent in 2012.