Pros
Compensation is competitive. Kindle is an interesting gadget. One has the chance to get involved in all layers of the product, and learn.
Cons
I stayed at Lab126 for a little over 2 years. Bad mistake. I should have left after the first year. Only a few and their friends are running the show. Expectation is extremely high and never never ending. Stress is maintained/entertained by managers in order to push employees on working always faster. On purpose, they arrange for what you write to be seen by everyone. Absolutely no mistake is allowed. If you make any, one gets humiliated by mean public/broadcast emails. Complex deliverables are often seen by unqualified managers as easy tasks that shouldn't have taken more than a couple days -- even if they are grossly in the wrong. In another post, someone refers to "Darth Vader" style managers. I cannot agree more. But they won't go anywhere. They are nurtured by Amazon corporate.