Since this is our second go at 30 under 30, there are some returnees from last year. Some are household names like Mark Zuckerberg, Lady Gaga and LeBron James, while others like Danielle Fong and Alexander Wang are superstars in their own realms. Fong, 25, is the cofounder of LightSail Energy, which is working to use compressed air to store energy cheaply and cleanly, recently raised more than $37 million from the likes of Bill Gates and Peter Thiel. Fashion wonder Alexander Wang, 29, was just named creative director at French house Balenciaga.
How good are we at picking tomorrow’s stars? Pretty good if last year’s list is any indication. Kevin Systrom, last year’s poster boy for the social and mobile category, sold his company to Facebook for $1 billion in April. British singer Adele, 24, went six for six in the 2012 Grammy Awards–and had a baby in November. New York City’s Chief Digital Officer Rachel Haot, 28, proved to be a hero-of-sorts during Hurricane Sandy in October when millions relied on the city’s social media feeds for vital information.