Adding to Frank's spot-on instructions: I settled on having a dedicated Finder folder on my system drive, and a dedicated Project in Aperture. This should give you a base to vary to your needs. The Finder folder is named "To Hot Upload to Aperture". It can be anywhere on your system. The Project is "_Hot Uploads". (The underscore forces it to the top of an alpha-sorted list.) My Sony software retains the setting of which Finder folder to put the images in. I set the Folder Action to delete the originals.
I take a picture. Camera sends image file to Sony software→Sony software puts file in "To Hot Upload to Aperture"→Folder Action forces Aperture to import file into Project "_Hot Uploads". In use I put the Sony software on one monitor and Aperture on another, with "_Hot Uploads" selected.
NB: Because you are importing this way, no metadata presets are applied.
When the session is over, I move all the Images into a newly created Project (I always put each Shoot in its own Project) and I run "Metadata→Batch Change" to apply my standard metadata preset (copyright and so forth). That leave both "To Hot Upload to Aperture" and "_Hot Uploads" empty, and ready for the next session.
Screenshot of Automator:
Message was edited by: Kirby Krieger -- screenshot added.