Knocks aside, I do like the general aesthetic and feel of the Fire. After using this device and then going back to the iPad 2, I was struck at how big and bulky Apple's tablet feels. This size and shape might very well be the sweet spot for many users, and since most people have never seen or used a PlayBook, the Fire should be a relatively new experience for them from a design standpoint too.
Minor complaints aside, my main takeaway from the Fire on the process of finding and purchasing content is this: Amazon has done it better and more elegantly than anyone else in the space right now, and I hope the competition follows suit.
There are some bright spots, like the use of tabs, but overall I was underwhelmed with browser performance.
Furthermore, because the Fire is on Android 2.3, many of the applications offered feel like glorified phone apps. That works sometimes, but often it feels clunky and cheap.