Are some rumors self-fulfilling?

So, this is a challenge to figure out - are rumors self-fulfilling prophecies? Consider this:
http://www.dealbreaker.com/bonusbumper/

I work for one of the firms included in there, and I know for a fact that the numbers at our firm have not been decided as yet. Some of my friends at other firms have told me the same - so who is promoting this propaganda? Do the analysts working at some of these firms really think that putting numbers out there would help them get bigger bonuses? Maybe it might have some impact, but for the most part, it would just be a rude awakening to some and a pleasant surprise to others. so, why do this? I'm lost!