As someone who is nowhere near skilled enough to do any such things, I am so impressed with these types of posts, very interesting stuff. I can also appreciate that you directly reported these vulnerabilities to FB.
As the past of being white hacker shows, keep hacking but shut up! Because even if you tell the author you find a way to get into their system and you havent cause any damage, they sure will come after you in a legal way.
In example herein, not only time after time the author proves that there are serious holes in FB auth system, but is also very happy to blog about it. You see, FB is publicly traded company. The management answers to stockholders and the board. If some Joe Hacker keeps finding holes in the system, someone somewhere reading that blog may be thinking of abandoning the FB platform due to it security layer looking like a swiss cheese. And management doesnt like that, because less users == less eyeballs for $.
My gut tells me, if this guy did not get offer to work for Facebook just yet, it means they are building a lawsuit against him, as you perfectly know FB TOS forbids anyone from fiddling with any of their URLs.
Not true: http://www.facebook.com/whitehat/
Only question -- who decides on what is "reasonable time", because something tells me its not a hacker, its Facebook itself.
Additionally, Facebook needs to be seen to be reasonable and have a proper 'whitehat' policy. If they start being mean and dictatorial here, then there will be a breakdown in social trust. People won't report bugs to Facebook, people will sell vulnerbilities on the black market. People will release exploits before telling Facebook. It will, eventually be bad for Facebook.
You kill someone, you get 5 years.
You hack something you get 10 years PER COUNT.
Pffff.
Nir in particular is one of our best supporters (rough rankings https://www.facebook.com/whitehat/thanks/) we certainly have no intention to sue him or anyone submitting bugs to us. He even stopped by our office last week to talk about bugs.
Some external opinions of our program - https://www.eff.org/deeplinks/2010/12/knowledge-power-facebo...