This was released what, last year? And really it's just documentary evidence like all the others of someone saying some outrageous [censored] happened, the FBI takes this evidence because they have to when a report is filed, and it's noted. The FBI is not saying "oh hey aliens visited us here's proof", it's just a release of statements a number of people made. Big deal.
This =/= proof of anything other than what we already know which is there's still no physical evidence to back up the claims of physical planes and physical beings. Nonetheless, without hesitation, alien conspiracy theorists will soak this up and it will present some more humorous, nonsensical alien fodder to parody for quite a bit of time to come, and some naive people will presume that because it's posted on the FBI website that the FBI is claiming there were aliens.

PS there's an alien living in my house, any advice on what to feed it?