Yes , apple is seeding its upcoming OS X Yosemite Beta , available from the Mac App Store using redemption code , if you have previously signed up for beta program then check your inbox for email from apple like this .
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System Requirements For OSX Yosemite Beta
- OS X Mavericks 10.9 or later installed
- At least 2GB of memory
- At least 8GB of available disk space
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Known Issue ( [official])
Safari
- Safari may hang when playing certain Netflix content.
iPhoto and Aperture
- iPhoto 9.5.1 and Aperture 3.5.1 are required on OS X Yosemite. Update to these versions from the Mac App Store.
- When entering edit mode in iPhoto, a black screen may be displayed instead of the selected photo.
- Photo Stream and iCloud Photo Sharing may not function properly when both iPhoto and Aperture are installed.
iCloud
- The shared purchase history page on the Mac App Store is disabled for Family Sharing accounts.
- iCloud Drive may appear empty in the Finder after first time setup. Restart to resolve this problem.
AirDrop
- AirDrop may not show nearby Macs.
- Sending files to another Mac using AirDrop may not work.
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Detailed Info On Official Site https://appleseed.apple.com/sp/betaprogram/redemption