Social media moves so fast, it's hard to keep up. Here are the week's top stories in scan-friendly format:

  • Twitter Finally Cracking Down on Spam
  • Mobile Web Traffic Centered Around Social Networking
  • Stats Provide Insight Into Twitter User Behavior
  • LinkedIn Gains Its 50 Millionth User


Twitter Finally Cracking Down on Spam

One of the major issues for those using Twitter is the increasing prevalence of spam advertising messages. These annoying tweets clutter your Twitter stream with unwanted messages that are thrown at you by advertisers, much the way you get spam in your email box. Up until recently, there has been no way of flagging spammers on the Twitter service.

Just yesterday Twitter introduced the ability to flag a spammer's account with a "report as spam" button inside that person's account. Twitter will then follow up on the report and delete the account if the flagged user is verified as a spam account.

According to a recent article, up to 3.75 percent of tweets are spam and the rate is increasing as spammers turn their efforts to the popular micro-messaging service as it gets more popular.

Mobile Web Traffic Centered Around Social Networking

New data from Openwave shows that those accessing the mobile web do so in order to connect with their friends via social networks. Four of the top ten domains accessed by mobile web users are social networking sites, pointing to the fact that the mobile device is being used in large numbers to keep up to date with their social circle's activities.

The most popular social networking services, according to the data, include MySpace, Facebook, Myxer and Plenty-of-Fish. In an odd note regarding this data collected in September, MySpace was more popular than Facebook in the timeframe specified.

Last month, Facebook announced that they are experiencing high mobile use with 65 million of its users accessing Facebook on mobile devices. Unless MySpace has a huge mobile following as well, these numbers seem a bit iffy. 

Mobile phones have long been a way to keep in touch with your social circle whilst on the go. It appears that this behavior has replicated itself with the introduction of data services on the mobile web. 

Between SMS, Facebook and Twitter -- what tools do you use on your mobile device? 

Stats Provide Insight Into Twitter User Behavior

A recent guest post over on TechCrunch gives some really interesting insights into the average Twitter user and their habits utilizing the micro-messaging service. 

Interestingly, Twitter as a service is starting to stagnate. The user growth, according to the author, has plateaued at around 8 million new users per month. There are a decent percentage, 14%, who don't have any followers, and three quarters of Twitter users have fewer than 10 followers.

Bottom line: if you're a Twitter user reading this article and you feel that your few hundred followers is a low number, your thinking is wrong. 

Digging in a bit more, the numbers show that the average Twitter user only has 42 followers viewing their messages. Also interesting, over 75% of all Twitter users have tweeted fewer than ten times.

So, looking at these data points, it is apparent that Twitter isn't a very sticky service for most people. The 'typical' Twitter user creates an account, follows very few people, makes a few tweets and then gets bored and bails on the service. 

This news might not be welcome to Twitter investors and others, but it just goes to show any organization who wishes to make in impact on the social web should have a multi-pronged approach and not depend solely on Twitter for their social media strategy.

[Editor's Note: See our popular article Top 5 Twitter Tools for Business.]

LinkedIn Gains Its 50 Millionth User 

As some social networks appear to be slowing in growth, one particular site just recorded a huge milestone. LinkedIn, the site for professionals who wish to stay connected to former co-workers and business associates, recently gained its 50 millionth user. Additionally, the professional's social network recorded a 5.68 increase in their monthly traffic. 

In a blog entry on their website, the company said it took them almost a year and a half to gain their first million customers, and only 12 days to gain the latest million users. That's some impressive growth, no matter how you look at it.

LinkedIn says that they have a very broad audience, with 50% of their users based in the United States and the other 50% being from other areas of the world. LinkedIn is a very focused social network that is based on maintaining and strengthening business relationships amongst professionals.

What is LinkedIn used for, practically? If you're job seeking, the site is a great resource. Also, if you are looking for like-minded professionals based on your interests or profession, LinkedIn provides groups to discuss relevant topics and industry news. 

LinkedIn has obviously done a great job of focusing on a certain segment of the social networking space and has executed well on creating a sticky user experience.