Cast your votes for the leaders, artists, innovators, icons and heroes that you think are the most influential people in the world. Though official voting for inclusion on the TIME 100 list has now closed (with Rain as the 2011 readers' choice), users can continue to vote for their favorites until the final list, selected by our editors, is revealed on Thursday, April 21st
Age: 24
Occupation: CEO of Tumblr
Previous TIME 100 appearances: 0
As a young Internet entrepreneur, Tumblr founder and CEO David Karp is in good company. At just 20, Karp created the trendy blogging platform after finding other services less than desirable. Sixteen million blogs later, Karp has elbowed out the competition in the blogosphere, one lolcat at a time.
