Canon today has released updaters for both the Mac and Windows versions of Digital Photo Professional (DPP) that bring the program to v2.2. DPP 2.2 on both platforms supports RAW files from the EOS Digital Rebel XTi/400D. It also incorporates a new Stamp tool function that applies the Dust Delete Data information inside pictures from that camera. Other changes include the ability to use DPP noise reduction on JPEGs or TIFFs and a revamped tone curve tool. The Mac version is the first DPP release to emerge as a Universal Binary for native performance on both Intel- and PowerPC-based Macs.
Other updates include ImageBrowser 5.7.2 (Mac), ZoomBrowser EX 5.7.0 (Windows), EOS Utility 1.1 (Mac/Windows) and CameraWindow DSLR 5.3.2 (Windows). While the release notes indicate that EOS Utility 1.1 for Mac is not compatible with Intel-based Macs, it's in fact a Universal Binary and appears to support tethered communication with a MacBook Pro here, so we're not yet clear as to what the limiting factor is in its use with the newest computers from Apple.
As is Canon's standard practice, most or all of the software updaters mentioned above will only run on computers that have Canon software already installed. All of the updaters are downloadable from most of the recent-model Canon digital SLR pages on Canon's Web Self-Service System website, including via the Drivers / Software link on the Canon EOS 20D page.
Back in August, Canon released WFT-E1A Utility 2.0 for Windows and Mac. It's available for download through the same path as the camera software updaters, including via the Drivers / Software link on the Canon EOS 20D page.