I'll focus on 10 ways in particular. Not all are exclusive to the past year, but many of the milestones from the past 12 months may well shape how we perceive the road ahead.
Democracy: The Green Revolution, Iran's populist attempt to reject the summer's election results, was a global eye-opener for how a tool like Twitter -- so easily dismissed as frivolous -- could change the world. The result may have been underwhelming, with Mahmoud Ahmadinejad maintaining power -- but for those who saw the tweets from Iranians, often retweeted wildly, it will leave its mark. Contrast this with other movements, such as when Philippines voters used text messages to mobilize and oust President Joseph Estrada in 2001. The Philippines revolution followed a peer-to-peer model. In Iran, though, the tweets were largely public, and instant commentary on those tweets was publicized further, shattering the barriers between those who were taking part and the spectators hanging on every character.
Death: We now mourn in public. Michael Jackson inspired millions -- billions? -- to grieve openly. Myself, I stayed silent on Jackson but had to express public disbelief over Billy Mays' passing. As I write this, friends and strangers are opening up about Brittany Murphy. The self-expression becomes more problematic when it gets personal, as a Floridian mom learned when she tweeted about her son drowning. This led to the headline "Twitter played no role in drowning of military_mom's son Bryson." We don't yet know how to grieve publicly, and many such as military_mom will learn that others aren't ready for it. But in time, perhaps even by this time next year, stories like this won't be newsworthy.
Sales: Dell has tracked over $6.5 million in revenue to Twitter. There are several morals to the story: 1) It's possible to track sales from Twitter. 2) It's still in its infancy; Dell earned $61 billion last year, so its Twitter sales will barely cover the Post-it notes used at the 75,000+ employee company. 3) Those are only the direct sales, and every time the press reports on Dell's model, some consumers will go to Dell's outlet site without bothering to check what's happening on Twitter. Bottom line, though, social media is making an impact on sales, and this year we finally started to measure that effect in earnest.
Searching: Google, Yahoo, and Bing committed to giving real-time search valuable real estate in their results pages. Sometimes it will be higher up and sometimes further down, and it will surely be much bigger than Twitter, but now it's here. Most people aren't going to think to search Twitter or Facebook or Foursquare, but they will visit Google or Yahoo or Bing, and they'll access the real-time links if they're relevant. We're still learning when it's relevant, but there's little doubt now that it matters.
Local marketing: So, how did you find out about that restaurant? Did you see a special for mayors on Foursquare? Did a friend check in via Gowalla and share it as their Facebook status? Were you walking down the street with your iPhone out while you augmented reality with Yelp's Monocle or Urbanspoon's Scope? Okay, augmented reality may be more gimmicky, but the social services are starting to help people find each other -- and help people find local hot spots. The fusion of mobile, social and local started to create real opportunities to change consumer behavior. What was true for early adopters in 2009 will apply to the fast followers in the year ahead.
Celebrity Access: In January, Ashton Kutcher joined Twitter. He was followed by Ellen DeGeneres in March and Oprah in April. We got to see what they saw, from Chris Brown's view of 90,000 fans in Manila to Chad Ochocinco's view of his opponents' football field. Vin Diesel posts a couple of times a month on his Facebook page, where he has over 7 million fans. And after Kanye West started a new Internet meme by grabbing the microphone from Taylor Swift at the MTV Video Music Awards, he apologized on his blog. Yes, we have ghost tweeters and plenty of opacity, but now that fans have this direct, personal, and occasionally even unfiltered access, it's not going away.
Fan participation: This summer, two amazing events happened in the arts world simultaneously. Here in the U.S., the rock band Of A Revolution (O.A.R.) crowd-sourced song lyrics on Twitter, crediting fans for their contributions to the song that became "Light Switch Sky." Meanwhile, London's Royal Opera crowd-sourced lyrics to an opera through Twitter. In the process, Twitter became a curation tool, and both curators here used other forms of digital media such as blogs and online video to further engage fans. Want to hook your fans? Give them a stake in the content.
Gift giving: Thought you were doing something special for a Facebook friend by giving them one of those little icons as a gift? How about giving them something they'd be really excited about, like an MP3, a charitable donation, or a "gourmet feast" gift basket? Yeah, that last one runs $85, but they are your friends, right? Today, those goods are provided through the Real Gifts application. Tomorrow, it may well be Amazon. What I'd really love to see is gift recommendations tailored to recipients' profile interests right when you're sending something virtual or physical.
News-sourcing: Journalists were among the first to embrace Twitter. Will they similarly lead the charge with Google Wave? They're starting to, anecdotally at least. Mashable loves covering these stories, from the Seattle Times posting a Wave to find a suspected cop killer to town squares hosted by the Austin American-Statesman. Google Wave itself may or may not be the platform of the future, but it's opened the door to news ways for the media to interact with their audience.
Gaming: In November 2009, over 6 million gamers (and their loved ones) bought the blockbuster "Modern Warfare 2." That same month, about 70 million gamers played "Farmville." I know I'm stretching comparisons here, but the notion of what a blockbuster game is continues to shift. Is it a game that millions of people pay $50 for right when it comes out, or a free game played by tens of millions of people, where a small percentage pay small sums over time for in-game upgrades? There's room for both models, and there's room for new thinking on what a successful game is.
That's just a taste of how our thinking changed this year, and it only leaves me hungrier for the new perspectives ahead in 2010.