We've been expecting something interesting to happen to the Apple TV, but with nary a peep out of Cupertino it seems that atv-bootloader creator Scott Davilla has been busy. We've posted about Boxee before: it's a media center application based on XBMC with a social networking spin. Previously it was limited to Intel Macs running Leopard (and Ubuntu Linux), but it's now been ported to Tiger. That means that it's compatible with the Apple TV, which runs a modified version of Mac OS X 10.4.
So what does this mean? Simply that you can now install the Tiger versions of Boxee or XBMC (for Mac) on your Apple TV. First you use need to use Davilla's handy atvusb-creator on your Mac to convert a USB flash drive into a patchstick. Then you just need to plug it into your Apple TV, wait for the patch process to complete, and install either Boxee or XBMC from within the plugin. In the end you get an Apple TV with all the extra functions of XBMC or Boxee including much broader codec support, the social networking features, etc.
The atvusb-creator is a free download from Google Code for Intel Macs. To use Boxee, however, you'll need to request an account at their site.