Twitter employees, naturally, use Twitter differently than the rest of us. But in what ways? Specifically, which apps do they use to tweet?

To find out, we used Twitter's API to analyze approximately 2,700 tweets from the Twitter staff list that were sent last week, including tweets from during the week and weekend, day and night. We then mined each tweet for its "source," so we can see which apps Twitter employee users tweet from, and compared this to the general public. The tweets we analyzed came from 54 different sources, ranging from Twitter's official clients to third-party apps like TweetDeck and websites like Yelp, Instapaper, and Quora.

The most popular client was Twitter's website, which accounted for 32% of tweets. That's pretty similar to the general public, which uses Twitter.com to send 35% of tweets, according to Sysomos. But that's where Twitter employees and the general public stop tweeting like each other. Among Twitter employees, Twitter for iPhone generated 22% of the tweets, about twice as much as the general public. Employees used Twitter for Mac to send 18% of their tweets, versus 0.4% for the general public. (Probably especially during the week, when Twitter employees are sitting around the office, tweeting at each other.) And while the general public uses TweetDeck to send 13% of its tweets, Twitter employees used it for just 2% of their tweets. Overall, Twitter employees use Twitter's official apps to send more than 86% of their tweets, while the general public uses them to send about 58% of their tweets. Given their employment at the company, and their role in creating and testing the apps, that discrepancy is not surprising.

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How much is a brand fan worth? It’s a question some social media marketers have been asking for a while, but research suggests many are moving on from the search for a hard number. According to a July 2010 survey of social media marketers by Millward Brown and Dynamic Logic, the most valuable aspects of social media brand fans go beyond anything with an immediate monetary value. Increased short-term and long-term spend on the brand were the bottom two results. At the top of the list were the fan’s value as a source of insight and increased loyalty overall. Advocacy and engagement were also important to at least three-quarters of respondents.

This suggests that, despite the real need for return on social media marketing investments, marketers are largely not worrying aboutputting an exact dollar value on each Facebook fan or Twitter follower—as if such an amount could be accurate. And they are keeping in mind some of the less-obvious qualities of brand fans, like as a source of market research. Still, these soft metrics can leave marketers unsure about their returns. Half of respondents to the Millward Brown/Dynamic Logic survey were uncertain about how much they were getting out of their investment in a social media fan base.

Less than a quarter thought ROI was good. Difficulties with these measures mean some marketers are still not trying to answer the question.

“The business question always comes up, but nobody can figure this out,” Maria Yap, director of product management at Abobe, told eMarketer about proving ROI for the company’s Facebook page. “For me, it’s about the value to the customer. I understand why companies want to focus on the business goals, but I put that aside. Let’s experiment. Let’s see what being here brings.”

While social media’s acceptance by and importance to the consumer has ramped up rather quickly, those who believed it had relevance to digital marketing were thought to be making a mountain out of a molehill. Well, that molehill has turned out to be more like Everest. A social-media strategy has clearly become a marketing must-have. These days, marketing channels, platforms, and tools that lack a social component--some way for consumers to actively engage with your brand--are probably doomed to failure. But what worked this time last year might not work today, for this is a rapidly shifting landscape that must be mapped out regularly. With this in mind, CMO.com decided that our wildly popular "2010 CMO's Guide To The Social Landscape” needed a fresh look and up-to-date analysis. We turned, once again, to 97th Floor, the SEO and social media firm that developed last year’s chart, to help you determine which social media tools and channels are your best bet in terms of customer communication, brand exposure, traffic, and SEO. The result? Our second annual guide for 2011.