I think everyone is still poking around in the dark.
I'm not surprised that Ballmer showed the HP Tablet at CES and declared it the HP Slate.
Probably a Big up your Wazoo to Steve Jobs just in case it was going to be the iSlate. I don't think Apple wants to jump into the waters with a diluted brand name since about 5 or 6 of the manufacturers at CES where calling theirs a slate.
As opposed to Apple releasing the iPhone like 50 years after everyone started calling their phones, um, phones?