I have to say that I, too, would have posted this news based on the source. The email was in fact sent from Apple’s email server to Apple employees and was then forwarded to Engadget from a trusted source. Ryan says “For a reporter, this kind of thing — an internal memo to a company’s employees — is solid gold” and I agree. This was almost as good as a formally issued press release.
Email: Easy to spoof.
Formal press releases from a major corporation: Difficult to spoof. (Can anyone think of an example of a fraudulent official press release from a major corporation?)