I think that's the problem, no one company is capable of doing it on their own. I don't think what Apple has done can be replicated now, in fact I don't think even they could replicate it if they were starting over.
A monoculture just can't compete at this point. I love WebOS, but I won't buy the phone. The apps aren't there like they are on Android, and as long as HP alone is selling it the platform won't be big enough to encourage that.