Maybe you're right, but Google has the personal data from me that they don't, across a variety of services that allow for integration and knowledge about me that is hard for me to really wrap my head around.

I've used this example before, but Google Now already recommends destinations based on what I Google Maps at my desk before I head out. It also knows what is on my "grab when I go by the grocery store" list before I quickly use Google Now and say "Google: note to self, pick up milk" and it's in there.

[soon] So now, when Google's autonomous car is driving me home and I'm watching the road attentively, Google Now pops up in Glass and offers to redirect the car to the grocery store most minimizing the way out of my route (or the one that has the best deals listed with Google Shopping, or that has the best coupons, or that Google Wallet has my rewards card for). And it reminds me to grab my milk. [/not yet]

And then on the way out of the store it again offers directions back to my house.

This is all there (except the Keep intuition bit that I sincerely hope is coming and will really prove Google Now). (And sadly, and I'm whining, but I didn't get into the super special Glass program :[)

Sorry, I've rambled, back on point: I don't doubt that those you list have the power and smart people to build the tech, but I don't think they have the data. I think Apple Maps was but a small example of the advantages Google has in areas of data.