My Equifax report shows "account information" by AMEX today. I have not applied for any of their cards lately and usually when a CC makes an inquiry it is shown as "New Inquiry" on the credit report. When I signed up for their credit cards, did I agree to some fine print that they can make inquiries as they please?

As far as I know, that is a standard practice; they routinely check your credit report to make sure your creditworthiness hasn't declined.

They oftentimes use a drop in your credit score to invoke the universal default clause of your cardmember agreement - which allows them to raise your interest rates at will.

There have been many stories done about how Joe Schmoe was late paying his Citi card - AMEX finds out he was late and raises his interest rates to the legal limit allowed by law. In AMEX's eyes, he became a higher credit risk (even thouh he may pay them on time), and by law they can raise your rates.

Ethical? Maybe not. But legal nonetheless. More about universal default can be found (of course!) on Wikipedia.

http://en.wikipedia.org/wiki/Universal_default

I had a bunch of pulls from AMEX and Citi, but thought they showed up in my "not publicly visible" part.

They will soft pull all the time to make sure you are still credit worthy, and you do authorize this somewhere in the T&C of the cards you have with them. The soft pull will not hurt your score and is not visible to anyone else.

I don't know what service you are using to review your credit, but I sometimes get strange alerts on True Credit. It could be Amex updated account information or something and they alerted you to something that really does not matter. Also, if you recently (within a couple months) did open a new account, sometimes it will take a while for the account to show on your report. The inquiry is instant, but the account information takes from a day to two months to appear depending on the bank.

If it is a new hard pull, you should contact Amex to check into it to make sure you don't have identity theft in progress.

Is that all they do? I don't mind my interest rates being raised since I always pay off my balance, but I would hate for them to reduce my credit limit.

I guess in theory they could lower your limits, too, though the beef most people have is with the interest rates (as a majority of people - myself NOT included - carry balances).

There have been stories about people being late with other non-revolving accounts (utilities, car payments) and this has triggered a universal default as well.

Congress is (supposedly) trying to make it so that the CC issuers can no longer do this, but as you probably know, they have a very powerful lobby in DC. One bright spot is Citibank, which recently abolished universal default clauses for their cards on their own - before the feds have a chance to force them to do it.