OK, have to start with compensation. The pay is simply too low given the background and performance they expect from people. To spend $80,000 on a brand-name B-school and end up with a $90,000 a year job just isn't worth it. This is New York, where a studio can cost $2,000 a month, and American Express's compensation just doesn't cut it. Also, HR openly admits (at least they're open about it) that the goal is to be no more than average for the industry. For a company that constantly preaches to drive for excellence, I think it owes its employees something a little better than mediocre compensation. Also, the health insurance HSA is poor. All it takes is one expensive prescription and that "savings" account is wiped out. The 401K plans stunk when they had Ameriprise funds, but they may be a little better now.
The jobs themselves, particularly in marketing, don't even really warrant the fancy degrees anyway. If you're smart and a quick learner, you can pick it up quickly. Most of the challenge is navigating the acronym maze to find the right person to get done what you need to get done, not actual strategy. Honestly, when you get a new boss, you may be much more of a subject matter expert than that person given all the movement in the company.
The culture can be a mixed bag. It definitely has a bit of sorority/country club vibe to it. You have to be very careful about what you say, because there is a lot of gossip. You can look forward to a lot of "Well, some of your colleagues say x" type of feedback from your manager, making you wonder what you did to deserve that kind of feedback when it seems like your colleagues think highly of you. You also pretty much have to do extracurricular activities such as employee satisfaction committees if you want to be considered a team player. Most of them are just bogus talking shops that waste time, but you better get on one, and if you become a Director or VP, you'll have to lead them.
Amex is very matrixed and consensus driven, leading to a very slow-moving, conservative culture. If you're looking to do cutting-edge, exciting work, look elsewhere. This is a place for people who don't rock the boat. The slow decisionmaking process always pops up in employee surveys, but it never changes. You will be doing a lot of "aligning", having meetings to prepare for meetings, meetings to recap meetings, and of course decks. Without Powerpoint, half the company would have nothing to do, particularly VPs and above. I actually think Sr. Manager and Director positions are more interesting than most VP roles because as Director or Manager, you actually do things, rather than talk about doing them. The majority of people in the company come from the same 5-10 b-schools plus a few different financial services firms and big consulting firms. This leads to groupthink, along with the obsession with meetings and decks. If you don't come from these places, you will have a hard time moving up and you won't get some of the special access these folks get (particularly B-school interns and recruits). Promotions are overwhelmingly from within, which is great for the most part, but as you get higher up, there is very little new blood or original thinking.
Oh, and if you hear the words "American Express Technologies" associated with one of your projects, run away, run far away. IT is bad at best, shows what you get by skimping and having your tech people in Phoenix instead of Silicon Valley or someplace with actually competent talent.
The review/rating/posting process can also be pretty phony and political, as it is in most companies. The "Goal" rating is pretty straightforward, except that if you exceed your goal but everyone else does as well, you may not get a top rating since ratings are based on a fairly strict curve. While you want the company to do well, ultimately, you don't want your colleagues to do TOO well, or you lose money. Brilliant system. On the one hand, everyone preaches the value of teamwork. On the other, you want to make sure your "teammates" do worse than you so you can get a better rating.
The "leadership" rating is complete New Age corporatespeak BS. It's basically based on how well-liked you are. If you're a rah-rah "I love the the Blue Box and every idea my boss has is fantastic" type, you'll be fine. If you like to question and are skeptical, you aren't a "team player" or you don't communicate well. Also, while HR talks a lot about 360 feedback and giving your manager upward feedback, good luck actually doing it. Amex managers don't tend to react well to anything but the most benign "upward feedback".
As I mentioned above, one of the really positive aspects to the corporate culture is the ability to move around. Just know that the politics surrounding performance evaluation apply to posting for new jobs. The mediocre performer who goes with the flow and is on a bunch of ESAT committees gets the rewards, while people who question things don't get very far. Understand that when I say "question things" I don't being contrarian for the sake of standing out, but pointing out legitimate issues that could hamper a project and offering alternative solutions. If you aren't high up the food chain, this kind of thing can be seen as not being a team player.
Also know that even getting a good rating doesn't guarantee you a promotion. People from the chosen B-Schools and consulting firms are usually favored. In addition to the rating you see in your evaluation, there is also a 'shadow rating' - the so-called 9-box, that you are not allowed to see. This basically determines how far you go in the company. If the higher-ups feel you're great at your current job but don't have potential for advancement, even outstanding performance may not help you.
Ultimately, the culture leads to people staying for a few years, and then most people get sick of the red tape and politics. Or, they realize that the company thinks they have maxed out their potential based on the 9-box and know they won't move up. You see very few older people in the Tower who aren't senior management. It's not so much the case at the service centers, where promotion isn't as big a goal.
To sum up, Amex is a good place to build your skills and brown-nosing ability, but it's more of a jumping off point for most than a home.