AFAIK back then they let you exchange the $999 kit for a normal iMac at no charge.
Now, you must return the kit and that's it. $499 just for using it for a year.
Even for that transition though, developers didn’t know ahead of time that they’d be able to exchange their developer kit for an Intel-based iMac¹.
See these comments on that page:
“One thing to note though is that you have to be in a $499/yr developer program to qualify for the $999 developer kit. Still, a pretty good deal for developers. Maybe they intended to give a production system all along, but didn't say so because they didn't want too many non-developers buying into the DTK.”
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“Yeah, I saw this earlier. This is pretty good.
Now I'm sorry I didn't join the program. I was thinking about it.”
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“Dammit!
I'm a developer in a small company and I originally decided not to order a DTK because of the $999 lease fee. That is, it was a capital purchase that depreciated over its short life.
If Apple had said they would swap it for an actual product that wouldn't have to be returned, I would have jumped at it.
As it is, I've now ordered an iMac Core Duo (for a higher cost) and my company's software may take longer than it otherwise might have with an Intel machine to test on. (That will depend on how it runs on real Intel hardware, not just with the Xcode checkbox flipped).
I guess they're rewarding early adopters, but the policy could also have caused a slow down in the emergence of universal binaries from small development houses.”
Cost back then was $999. Now it's just $499