Still, everything should be taken with a grain of salt.

Think about it, they seem to be experimenting with perks. What if the perks turned out to be useless, or break gameplay somehow? What if, in response to that, they cut perks entirely? Hell, what if the concept of perks in Halo was simply fan speculation that started with a rumor and snowballed entirely from there, and is yet accepted as fact?

Well, everyone who looked at these images and read those posts would be disappointed when they get an official update detailing game features and the perks are missing. This would cause an unnecessary negative reaction from the fan base, because they didn't stop to think, "Wait, this is a leak of a game in development. Everything here might not be there later."