Edit: Might be worth noting that logging out of FB "fixed" this for me. (But I had to go back and re-open all those tabs.)
works fine for me, perhaps because I have never used Facebook to log into it.
AFTER EDIT: Replying to the kind reply to this comment, I am ALWAYS logged in to Facebook (with AdBlock Plus and Social Fixer and Ghostery activated, using Chrome), and I was surfing all over the Web completely normally while sites were reported to be redirecting. So maybe something different about my set-up protected me from the problems many other users observed today.
I absolutely love Ghostery and other related tools.
EDIT: By the timestamp on your comment, the issue appears to have been fixed, anyway.
Adding the JS file is simple and up until now has always worked. If it ends up driving tons of traffic back to your site it seems worth it.
(N.B.: I work on Persona, and it does have a centralized fallback for bootstrapping browsers and identities. The difference is that the centralization is temporary, optional, and automatically goes away over time.)
Facebook Connect was deprecated in 2010
http://mashable.com/2010/04/21/facebook-kills-facebook-conne...
from the same article: " Instead, the company is standardizing the interactions between Facebook and third parties via Facebook's new Open Graph protocol and the OAuth 2.0 standard."
And, they are surely breaking.
I poked around a bit. When you include Facebook's JS, it calls on a PHP file which (inter alia) returns a <meta> tag with a redirection instruction taking you to the broken page.
I can almost guarantee that the folks that implemented FB connect didn't understand that the failure mode could forward all traffic to FB. I have no idea how that could become a rational design decision.