Cancelling the card has been the cardholder's tactical weapon against that nonsense. It's still a hassle for the cardholder, so I'm left wondering how much of an actual problem it is that people are canceling entire credit card accounts just to wiggle out of a contract.
And, in the case that people do that, the merchants have recourse through either collections or court. If enough such charges go to collections, the cardholder loses the ability to open new accounts.
If people are no longer able to cancel their credit cards as an item of last resort, then the merchants are left with all the leverage. Arrington's natural response to that -- as I suspect will be most other peoples' -- will be to stop using their credit card.
I don't think we want that to happen.