Amazon.com treats its employees like dirt. i worked in retail downtown [seattle] for several years. i started when the economy started going south and watched the company change with it. you got a really good sense from management that if you didn't like the way you were treated, good luck finding another job. and better get used to having your blackberry on 24/7.
the problem is simple = poor, untrained managers. some of the worse i've ever experienced. amazon corporate is not large. middle management in seattle is only a few people removed from jeff bezos and his "S-team". if you are some joe-blow manager at amazon you are within reaching distance of being a millionaire (stock, not salary). they are the problem and the rest of the staff suffer because of their desire to be noticed by jeff.
the turnover rate at amazon is ridiculous. it's so bad the SDE's created something called the "old fart tool" based off your employee ID so people that have been there a while can verify just how lucky they are. i checked mine at 20 months in, 4 months before being let go and it showed that of all the people hired AFTER me, 32% were still employed. 80%+ of the company has been there less than five years. what does that say?
oh and HR is a joke. if you have any problem with anything at amazon don't think for one second HR is there for you. they are there strictly to protect management from lawsuit. period. they are as effective at human resources as the management is at managing.
i'd be willing to bet most of the positive reviews on here are new employees or the managers i refer to above.