Most Important Theme Feature Of 2012?

WPHub.com is hosting a poll right now that asks, What Has Been The Most Important WP Theme Feature In 2012? Out of the choices listed, I voted for Responsive Design because of the prolific usage of Tablets and smartphones versus the traditional desktop computer. On that note, I think it was a very wise choice to have the new default theme in WordPress 3.5 have a responsive design by default. After you place your vote, feel free to come on back in the comments section and explain why you voted for that choice.