Social media was inescapable in 2012. Facebook ballooned to 1 billion users, Instagram surpassed critical mass, Twitter took over the presidential election, and Pinterest gave us something new to root for.

But we also saw outlandish lawsuits and a botched IPO, ensuring that 2012 will be remembered as a year of both extreme highs and lows in social networking. What follows are our top 10 picks for the social media-related news stories that defined the year.