I haven't yet signed up for the beta. Can I? How?
Apple says that the first one million people to sign up for the Beta Program will be accepted. Just go to the OS X Beta Program page, click the Sign Up button, and follow the steps. You'll need a valid Apple ID, and you'll have to agree to the terms of Apple's OS X Beta Program Agreement.
The Yosemite beta will be free to download for program participants.
I applied for the Yosemite beta program a while back. When and how will I find out if I was accepted?
The first one million people to sign up are automatically accepted. Apple says that once the public beta is ready, those people will each receive a redemption code for downloading the Yosemite beta installer from the Mac App Store. You just install it and start using it. (Of course, it's a bit more complicated than that, as we explain below.)
I previously signed up for the OS X Beta Seed Program. Have I automatically been enrolled in the Yosemite beta?
No. The OS X Beta Seed Program, which currently allows users to install pre-release versions of Mavericks (OS X 10.9) updates, is separate from the Yosemite beta program. You can sign up for both programs, but just because you're part of one doesn't mean you'll get to participate in the other. You'll need to sign up for Yosemite separately and hope that you're one of the first million people to do so.
I'm a member of the OS X developer program. Do I need to sign up for the Yosemite beta, too?
Probably not. Though Apple says that "there is no guarantee that participants in the OS X Beta Program will be given access to the same updates of OS X that the Mac Developer Program receives," we suspect that if there are differences, developers will get access to new beta versions before the general public, and will possibly receive more-frequent updates.
Do I get anything out of being a beta tester?
Other than the satisfaction of knowing that you helped make the official release version of Yosemite better for millions of people around the world? No. (Yosemite will be free, so the usual perk of being a beta tester--a free copy of the final software--isn't compelling here.)
Can I talk about the beta publicly?
According to Apple and the license agreement all beta testers must agree to, the Yosemite beta is "Apple confidential information." By accepting those terms, you agree not to discuss your use of the software with anyone who isn't also in the OS X Beta Program. That means no blog postings, no screenshots on Twitter, no showing your neighbor the cool new stuff your Mac can do.
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