William Loyd is correct - Your can achieve the same thing using the cannon utility and simple automator script. You can get the script at
http://www.apple.com/downloads/macosx/automator/aperturehotfolder.html
I understand it might not be integral to Aperture and sure some might say that Lightroom can do why not Aperture, but it doesn't right now. So.....
I have used the automator script and the cannon utility on an almost daily basis and I have essentially tethered my camera. It works well and is simple to setup. I don't agree with other posters that it is unreliable or cumbersome - how so?
Ultimately if you want automatic import of your images into Aperture this is currently the way available.