The guys & gals (Hi, Jane!) at WordPress still havn’t, as of August 7th, 2012, released the predecessor to their default theme “TwentyEleven”. So I made one that will stand the test of time, it’s not a full blown new theme, rather a child theme that adds responsive design to support mobile and tablet browsers and some other tweaks that I believe improve user experience.
You can find the repo on github https://github.com/montanaflynn/TwentyFifteen
And your probably looking at this theme.
They finally did release http://wordpress.org/extend/themes/twentytwelve, fitting as that may be considering how it’s now February of 2013