After the Gmail get it's themes, and now it's Google Reader turn to get a better look. The visual clutter is removed and brings more space.The old rounded corners, drop shadows and heavily saturated colors are removed which means a softer palette, faster components and a fresh new look.Google Reader adds collapsible navigation to each section of the sidebar, improved options for sharing items with friends, and the option to hide unread counts for any section of reader, just like your friends' shared items (Sometimes I want to hide it). The Feed Bundles are also added more so that you can learn more than you ever wanted to
( NASCAR, yoga or knitting). Here is some of the detailed screenshots of it's features

Hide Unread Counts

More feed bundles!