I'm writing this from my iPad. I don't think Jobs is at all on the defensive, I think that's more true of the Andriod community after he spoke. Steve simply took control of the message. He was fed up with Google labeling iOS as closed and Android as open. They were controlling both sides of the conversation and he sought to put an end to it. From the discussions here and elsewhere on the Web, he was successful. He has turned the table on Google and now there's doubt about Android's openness claims. His terms, integrated to describe iOS and fragmented to describe Android, will be the new labels.
I also think he killed the 7" tablet in his statements. He is a well respected CEO and his words have impact, more than anyone at Google or Adobe. There's little doubt Android's phenomenal growth will be slowed significantly, when iPhone 4 joins iPad on Verizon. It's going to be a bloodbath. Don't lull yourself onto thinking otherwise. Just my two cents.