Facebook's comments do not discredit the leaked materials because even if you treat Facebook as trustworthy, the NSA slides explicitly encourage analysts to use

Facebook's comments do not discredit the leaked materials because even if you treat Facebook as trustworthy, the NSA slides explicitly encourage analysts to use a combination methods including "UPSTREAM" data collection ("You should use both", the document reads). The only really interesting revelation here is Facebook's confirmation that the FISA court is bundling approval for multiple users into single warrants. And if we assume that the vast majority of requests are for single users, this is a non-trivial admission. With those numbers, there could easily be a handful of warrants used to grab information on thousands of users.