From the first time I heard/saw the branded button, I was put off by it. It was by no means gonna stop me from getting the phone though.
Now, after just playing with one in a store for a good while, I will say that I totally forgot the branding was there. Compared to the awesomeness of the device & the beauty of the screen, I don't care about that button at all anymore.
Now I just have to make it till Thursday morning without the phone.