I've started downloading it. I don't think you have to use this link, I've started my download from the Member Center[0]. It gave a "redeem code" and started downloading.
Edit: This is only for people who are members of the Developer Program. I only pay for iOS and I have access to OS X too so you probably only need membership from the one of the developer programs.
[0] https://developer.apple.com/devcenter/ios/index.action
Edit: This is only for people who are members of the Developer Program. I only pay for iOS and I have access to OS X too so you probably only need membership from the one of the developer programs.