Everyone (or almost everyone) loves social media but there are plenty of pitfalls to be aware of, especially in areas where it overlaps with the professional world: employers vet potential employees through their social media profiles, while big companies worry about security breaches enabled through casual social network activity. Hewlett Packard is learning about the latter this week, following what appears to be an inadvertent leak of its closely-guarded plans for a cloud computing service via LinkedIn.

Social media ad spending will increase at a cumulative annualized rate of 31.6% per year from 2010-2015, according to a new forecast from BIA/Kelsey, which sees social media ad revenues jumping from $2.1 billion in 2010 to $8.3 billion in 2015. Four years from now, BIA/Kelsey expects that social media will contribute 21.9% of all digital advertising revenues -- up from practically nothing just two or three years ago.

Not since the suicide of Adolf Hitler on April 30, 1945 have so many people been so happy over the death of a single man. The killing of Osama bin Laden -- almost ten years after the terrorist attacks on September 11, 2001 -- is one of those events for which people will long remember where and when they heard the news. I heard the news from a Facebook update via a mobile device, or rather my friend's mobile device. We were immersed in a long movie -- the Godfather, fittingly, just after Michael Corleone exacts revenge against the man …

Social media is coming to vending machines, courtesy of PepsiCo, which unveiled a new touch-screen interactive social vending machine at the National Automatic Merchandising Association conference in Chicago. According to InformationWeek, the machine -- developed for PepsiCo by DCI Marketing and Protagonist -- allows individuals to buy drinks as gifts for friends, who receive redeemable codes via text message. The person buying the gift just has to enter the intended recipient's name and mobile number, along with a personal message - plus a brief video message, if they wish. The recipient can redeem the code whenever the mood strikes.

As noted in a previous column, Facebook seems to be prepared to throw free speech under the bus in its campaign to bring Facebook to China, where the social network is currently blocked. Aware that agreeing to censorship will open it to charges of collaborating with an authoritarian regime, Facebook may try to preserve a modicum of integrity by alerting users to the fact that the Chinese government requires it to engage in censorship. But this compromise -- in reality a fig leaf as it abandons its own core principles -- may still come up short.

If anyone needed more proof that social media is volatile and unpredictable, this week should settle the question, as two erstwhile giants of the scene -- Friendster and MySpace -- prepare for humiliating denouements. Friendster, probably the first widely popular social network back when it launched in 2002, has since basically become a punch-line (literally, after Tina Fey took a swipe at it on "30 Rock" a couple weeks ago). Now Friendster is throwing in the towel in the U.S., announcing that it will delete all user accounts and content on May 1 as it prepares to reinvent itself as …

Don't call it a killer app, but social media is being adopted by yet another unexpected profession: epidemiologists who study the origins and spread of disease, and who are now using online networks like Facebook and Twitter to identify and communicate with affected individuals.

I think it's safe to say that many people are stupid, and even people who aren't stupid often do stupid things. There's no other way to explain the cavalcade of idiotic behavior enabled by social media. My favorite stupid social media trick: people posting incredibly offensive or inappropriate content (photos or text) on social media sites and losing their jobs because of it.

People are using social media in all sorts of unexpected ways: Law enforcement to publicly shame criminals, divorce attorneys to find evidence of infidelity. Now debt collectors are searching social networks.

A couple months ago I wrote a post suggesting that in the wake of the Egyptian Revolution, major online players like Facebook and Google should embrace their role as catalysts for political change by helping activists create tools for organizing protests and monitoring their own governments. But Facebook, at least, appears determined to turn its back on the cause of freedom in countries suffering under authoritarian governments.