Originally posted by abruzzi Aperture has a "retouch" tool that is great for dust specks. It basically works like the spray can tool, but uses surrounding color and pattern to do the fill. It even clones the grain. When the dirt is over a complex background, its noticeable, but on images like yours it would be mostly undetectable. I'm sure adobe and others have a similar tool.
Edit: attached a quickie 2 minute cleanup with that tool.
Hahaha - I didn't read far enough down before I popped it into LightRoom for a quick clone-tool session. Also about 2 or 3 minutes spent here. Both do a great job.
(Sorry about the border @timw4mail ... it's in my export settings)