From a hardware standpoint the Nook isn't that far off of the iPad. Any differences in feature set are largely due to them running some custom version of Android which probably cost a lot more than running stock. Just slapping Froyo on it would have made the feature set as comparable as you could get.

So in terms of pricing (and probably only pricing) it's a fair comparison. It illustrates that vendors could compete with Apple on pricing if they wanted. I think they're quite wise not to, everyone saw the race to the bottom on PC margins that happened in the late 90s and decided they'd opt out this time around.

You're right about the phones, others are subsidized, though usually with an upfront fee rather than an ongoing. The rumors in the early days were that Apple's monthly fee is much more than most other phones get, and that's why AT&T got them over Verizon, but who knows.

Many PC vendors have service at least as good as Apple's. I've dealt with both HP and Apple, they're pretty comparable. And with HP you never have to hear the term "genius bar".