Contradiction wise, Mantle can be open sourced and an open standard/will only work with GCN hardware.
Is exactly the API for one or more consoles/Is not the API for consoles.
Will completely replace drivers in the windows environment for specific hardware/will have a hardware abstraction layer
That sort of thing.
Some of it is definitely people in this and other forum environments embellishing. However, I can't help but feel that statements are being made as intentionally vague yet suggestive as possible, so as to encourage this sort of assumption without having to worry about being proved technically wrong later.
A complete technical briefing, white paper, or similar from AMD would of course solve these issues, but that seems to be something of a pipe dream. Rather than just explain - "This is how Mantle works, here is a sample of API execution, here is our plan for licensing/releasing extension sets... etc" there is just instead this giant, nebulous cloud of claims. The lack of certainty and particulars in the information actually being shared means that people are filling in the gaps in that knowledge with assertions ranging from hailing Mantle as the greatest acheivment in computers since Floating Point Operations, all the way to people that are dismissing it out of hand as a complete non-starter.
For such a small amount of actual information having been released, it certainly has generated a heck of a lot of page hits, forum messages, and completely flooded news reporting throughout the holidays. Unfortunately, because of the polarized nature of this particular hobby and, frankly, this forum in particular, all of this delay in details being filled in has just left everyone time to drive way out to the extremes of rhetoric.
Hope that clarifies.