It's the time of December when we look back at the past 12 months, as well as ahead to a new year. Newspapers, magazines and news websites will present lists and galleries of 2012 headlines that mattered most, as some already are doing. The presidential campaign and Barack Obama's second-term victory are on all lists, naturally, as is the devastating East Coast "superstorm" in late October known as Hurricane Sandy. CNN lists Sandy as its most-viewed online news story this year. Yahoo says the presidential race was by far its most widely searched news topic.

Heavy attention also focused on the Summer Olympics in London, where U.S. athletes won 46 gold medals – including in widely watched events such as swimming, gymnastics, soccer, women's volleyball and basketball (men and women). Other high-interest news subjects include struggles in Syria, Libya and Egypt, as well as the continuing war in Afghanistan. Here at home, leading events included a Supreme Court decision upholding President Obama's health insurance reform known as the Affordable Care Act and a fatal Florida shooting in January of Trayvon Martin by a neighborhood watch patrol member now awaiting trial.

Not all memorable news of 2012 was serious. Headlines were made by South Korean pop singer Park Jae-sang, better- known as Psy, as he spread "Gangnam Style" around the world and watched his video become YouTube's most watched ever (more than 932 million times). Prince William and Kate Middleton of Britain earn a place on many lists because they announced her royal pregnancy. The iPhone 5 release in September ranks at or near the top of technology news events. This Wednesday morning on the Today show and Twitter, Time magazine will announce its Person of the Year cover selection as that issue goes to press.

Top Yahoo search topics: Election, iPhone 5, Kim Kardashian, Kate Upton, Kate Middleton, Whitney Houston, Olympics, political polls, Lindsay Lohan, Jennifer Lopez.

Time 'Person of the Year': "We’re trying to make a decision about who best represents the news of the year. . . . Ideally, we want our Person of the Year to be both a snapshot of where the world is and a picture of where it’s going. -- Radhika Jones, executive editor

Facebook's most popular people: President Obama, Mitt Romney, One Direction (band), Tim Tebow, Eli Manning and Peyton Manning (tie for fifth), Madonna, Honey Boo Boo, Jeremy Lin, Paul Ryan, Phillip Phillips. (Based on number of mentions in posts.)