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I remember I paid $99 for a standard account when the 3.0 betas and SDK came out last year.
 
You can be a member at the ADC site for free.

It is $99/$299 to be a member of this and get your apps published.

You can freely download the SDK, but it is $99/$299 to get the betas for the iPhone or iPod Touch and then be able to publish your app.
 
I signed up for an account without charge back in November or early December. I downloaded the SDK and I've been working on a project for a while. I didn't even know they'd ever charged for it.

And, yes, http://developer.apple.com/ is the site I've been logging into since November or December.
 
I also thought it was always $99.

It was originally free to join the ADC, download the SDK, write programs, and test them in the "virtual iPhone" simulator. I did that for free as well.

If you wanted to debug them on your own phone, or if you wanted to submit any apps for approval on the iTunes App store, you had to pay $99 to enrol in the developer program.

The original hyperlink to download the standalone SDK by itself has been taken offline.

The page linked by the OP lists the $99 Standard and $299 Enterprise developer's programs, but doesn't list any option for an SDK-only download. Anyway, if you follow the links from that page, you're redirected to a page that says that enrolment in the iPhone developer program has been temporarily shut down while they update their system.

IMO there's no use speculating further until those pages are brought back up, especially given the fact that they probably won't be down for too long.
 
I'm an iPhone developer, you CAN do it for free... but the only thing you can do with it is test your app in the simulator. You have to pay at least $99 in order to test on your iPhone and publish to the store.
 
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