re: Will canceling an Amex card hurt my credit?

Cancelling credit cards isn't really a good idea. A large portion of your credit score is based on credit longevitity. Even if you rarely use it, it is good to throw a couple of charges on it a month to keep it active to build the longevitiy. With that being said, you have only had the card open for 15 months and closing it will only possibly lower the score temporarily. After a few months of paying other bills on time, your score will be back to where it was. If you aren't looking to obtain a loan in the next few months and don't want to pay the 175 a year, it certainly won't kill your score to close it, but credit longevitiy is definitely a factor.

As far as the other poster saying it will hurt the amount of credit you have open. This is a true statement, but you can remedy that by requesting a credit line increase on your other cards.