I read recently that Chase/Bank One has decided they only want a certain bank customer with a certain amount of money in their accounts and certain assets; the article I read (and I can't remember where I read it--I think it was actually in the mainstream newspapers a year or two ago) stated it would take them a while to go through their accounts and figure out just who they wanted to keep (I'm taking this to mean, how much money their account holders have in the bank and who doesn't have enough/should be eliminated).
You can go to the bank and ask why--and they're right; they don't have to tell you.
It sounds like they've finally decided how much/what kind of money/accounts/assets they want their bank customers to have. Anyone else who doesn't fit their bill is being axed. Apparently, you're not "rich" enough for them to keep. Or maybe it's, you're not "poor/indebted enough."
After reading some of the other comments here and going to some of the off-site links provided, I would heavily bet on the fact that Chase is only interested in those who have a lot of debt/outstanding fees/don't pay their credit cards in full, because that way, they make a lot of money off them in terms of fees.
In the world of banking and money, the BEST way to use a credit card is to pay what you owe on it in full every month. That's the best for YOU. However, it's not the best for the bank(s); they don't make any interest on you if you don't hold over money from month to month.
I've currently finished 2012 with being able to pay my VISA bill in full 11 out of 12 months of the year. In fact, as of two months ago, my bank actually lowered my interest rate by 10% points. Why? Because they're hoping that I'll suddenly splurge and run up a big credit card bill and won't be able to pay if off the next month so they can make interest off my account!
I'm running my account as an experiment to see how long the bank will allow me to pay off my account every month before they say something or decide to drop me because I'm not making them any money. Sad, isn't it, when we should all be better stewards of our money and our debt and the banks don't want to allow that? We just paid off my husband's huge VISA card debt and will start paying his bill off every month as well, starting this year. We both are with the same bank (which I've been with since I was 18 years old--27 years); wonder how long it'll be before we're "kicked out" because of them getting no interest on our accounts?
Find yourself a smaller bank, maybe a credit union. You'll find they are a lot nicer and will appreciate you and your money.