Apple has pushed out updates for iMovie and GarageBand to add compatibility with OS X Yosemite and add new features for both apps. GarageBand 10.0.3 introduces a new Bass Amp Designer, tweaks to the zoom function, a new template for recording vocals, and other changes.
iMovie has also been updated with a new interface that fits with the new design in Yosemite, as well as to add support for new features like the ability to create iPhone app previews for the App Store and tweaks to the adjustments bar and other changes. There are also new options for exporting videos as custom H.264, ProRes, or just audio tracks.
The full logs for both apps are below: