Over at Hart’s Blog, he’s reporting that “Soundbooth seems to work fine in Leopard but there are two things that might get you into trouble.”

First, Soundbooth will likely crash if you select “System Default Input/Output” in either the Soundbooth preferences dialog or in the recording dialog. This is not selected by default, and if you select any other choice for your audio hardware Soundbooth still works fine.Second, Soundbooth may crash when you quit the application if the video window open and undocked. This crash doesn’t appear to hurt Soundbooth or your system (since it only happens when you’re quitting the app) but it can be annoying.

“Our team is working on a patch right now and we expect to have it out and available in December. Until then, if you avoid the two scenarios above you shouldn’t have any problem with Soundbooth in Leopard. You can check out the Adobe Leopard FAQ for more information about all of our products.”