[joe_bloggs]

Incidentally all the Facebook notifications and deal emails I receive on my gmail inbox have this warning message in red: "Warning: This message may not be from whom it claims to be. Beware of following any links in it or of providing the sender with any personal information. Learn more" and all the links are blocked.

This is either a really dumb spam filter or a cheap anti-competitive ploy by Google. (I doubt if it could be the former.)

[zheng]

Never had this issue, so it sounds like an error. Or maybe google is just messing with you ;)

[joe_bloggs]

Here's a screenshot: http://i.imgur.com/KYdUb.png

This happens consistently for any Facebook notification email or Deal email. Also, all the links in the email are blocked.