No one has NOT confirmed it wouldn't be called Z28. All we have is an internal codename of "HP". I guess to the non-engineering world that sounds important, but it isn't. When's the last time you fired up your install of Windows Chicago or Windows Longhorn?
Internal codenames mean nothing. The only people that seem to be excited by internal codenames are people who don't understand how little they mean to a final product.
OldJedi: Way too soon? It's been in development for 2 years, who says it isn't ready?
toesuf94: we have not been told time and time again it won't be called a Z28, where did you get that from?
I have little faith in rumors, but I certainly have even less faith that an internal project codename will be the final-to-market name. That's just really, really silly.