Apple has released GarageBand 2.0.1 update in your Mac OS X Software Update:
GarageBand 2.0.1 addresses issues with duplicating tracks, playhead snapping to grid, joining software instrument regions on adjacent tracks, making precise adjustments to volume and pan settings, and converting Software Instrument Apple Loops based on drum sounds into Real Instrument Apple Loops. It also addresses an issue where recorded Real Instrument regions may not properly adjust to changes in the project key.
Of note, Nine Inch Nails recently released a GarageBand file of their recent single, "The Hand That Feeds", on their website.