WordPress 3.8 is the current core release version. The most current default theme is now Twenty-fourteen.
WordPress continues to evolve and with it so does the version of their latest default theme. The newest version, Twenty-Thirteen, is currently only available within the WordPress 3.6 beta. The following article gives you a preview of the current release of this theme.
Previews of the Twenty-thirteen Theme for WordPress
The new WordPress Twenty-thirteen theme departs from the previous photographic elements that were the principal focus of theme. Instead, they have a colorful header with fallish colors using multi-layered shapes. The following screenshots give you an idea of the theme and how it will appear when activated within the WordPress interface.
The screenshot at right shows the header, body, and footer sections for the new theme.
The capture at right shows the appearance of the theme in the backend.
Click on the HEADER button and you will get the usual options to change theme appearance. By default, you will see three different header patterns, plus the option to select a different color.