I don't know if enough about doomsday to say for sure one way or the other.
What I can say is that in my experience on the internet, 99% of the time that people claim to be insiders or have special knowledge about something, they are lying. When someone does have special insider knowledge, it is obvious and they never have to try to prove it by citing to unnamed sources.
Doomsday takes the same tact as all the other liars that I have encountered on the internet: have an undisclosed connection to undisclosed people/sources who all like to leak spurious (at best) predictions which are not any more informed than the opinions of posters here or the press. Now, the fact that he follows the same course as all of the other liars I have encountered on the internet doesn't in and of itself make him a liar too. All it does is suggest the proper view of him is a skeptical one.
He can prove me wrong. If he ever shows up wish some insider info that is orthogonal or contradictory to the conventional debate, and it turns out to be true, then I will accept him. But as long as he makes vague predictions from his unnamed sources that all center around the popular discussion, I'm not going to view him as anything other than an internet blowhard liar.
What I mean by this is the following: if, for example, the popular debate is that Houston is going to take Reggie Bush or trade down, and he rolls in and says "my source says they are going to take Ferguson" and then Houston does that, then I will believe him. Because then he is predicting something that isn't self-serving due to its obviousness. Or, for another example, if he says that "according to me source, team X is talking about trading player Y" and no one else is talking about team X and no one is predicting player Y will be traded, I'll believe him. Or to put it another way, my claim to have insider info isn't proved by my prediction that "my sources say the sun will rise tomorrow."
Until then, he is just another internet liar using made up sources to reinforce his preconceived wishes/beliefs.
But seriously, ask yourself this: why does he feel need to tell us that his information comes from sources? It's called bolstering. That is, it is said to make you think he might have special knowledge or that his opinion has more power than your's. If he does have insider info, and his only goal is to share it, then he can just say "The Patriots will sign Adam V. tomorrow." But sharing information is not enough, he wants you to believe him that he is an insider himself.
So, despite rambling for a bit, I will just say that if I was a betting man, I'd bet heavily that this guy is just another internet blowhard and liar. But as I said, I will allow him to prove me wrong.
