DaisyDisk has gained the ability to scan multiple disks simultaneously. It also has in-app deletion, which was a needed feature. Just grab files and drag them onto the bull's eye in the bottom left corner. If you change your mind, expand the menu and drag the file you want to keep out of the listing. This will enable you to not only delete a number of files at once, but easily see how much space you're gaining at the same time.
Additional changes include support for multi-touch gestures, scanning as Administrator and even Twitter integration. However, localization has been temporarily dropped.
DaisyDisk is US$19.95 through its website and $19.99 through the Mac App Store. Those who have version 1.x and want to take advantage of upgrading for $9.95 need to go through the website. Those who bought DaisyDisk before Oct. 15, 2009 and after Sept. 1, 2010 will get the update for free.
Note that the version available through the website has some features that are not available through the Mac App Store version -- mainly the 'scan as Administrator' mode. The stand-alone version can be used on Leopard, while the Mac App Store version requires Snow Leopard. Those who bought the app through the Mac App Store and want to migrate to the stand-alone version can send a copy of their receipt to DaisyDisk's support team, and they'll send you a key for the stand-alone version.