"Game developers requested Mantle themselves. That's the key difference. The industry told us they want it... Johan from DICE sat across the table from Matt Skynner, the GM of our graphics business, and explained how he wanted a close-to-metal graphics API. Matt said "we can do that," and the rest was history. Other devs are very excited when they learn about what Mantle is capable of, and how Mantle can help them bring their game to life on the PC." - AMD
I remember them saying this in the blog post they did about Mantle. But of course many of the Mantle doomsday naysayers conveniently ignored that, just like they will ignore this quote as well.