They use software to drive their hw sales....
This is probably where Aperture users should place their greatest hope. Back when Aperture was first released, a lot of Mac users (like me) were cut out because Aperture demanded CPU and video card power that was only at the top end of Apple's hardware line. Back then Aperture was must-have, so many users upgraded their systems to run Aperture. Like you said, software drove hardware sales.
Well, now the Apple pro line is all due for a refresh. The new Core i5 and i7 chips are so powerful that you now have iMacs that outrun Mac Pros, that is obvious to everyone. CPUs of this new generation
have to end up in MacBook Pros and Mac Pros soon. Don't be surprised if Apple rolls out new hardware sometime this year, driven by the latest CPUs, and at the same time comes out with an amazing new Aperture but the catch is it "runs best on our latest hardware" so give us money now and we'll gladly upgrade you...
So maybe Apple is setting up Aperture to drive their pro hardware again, when both are ready.