Yeah, K9 would have been a killer name for these chips! Imagine Greyhound, Pitbull, Bulldog, Rotweiller.
That would have been awesome for marketing, provided they are as revolutionary as I think they are. But from what i've read, K9 is actually the name given to dual core K8's. Of course I could be completely wrong, but it does make sense. And K8L for mobile, which I do believe was mentioned by AMD themselves also.