I held the backorder at the time of auction (and still do for now) and decided not to bid. It's a nice name in itself, but let's face it - almost nobody's going to sit at their computer now and type "creditcard101" when they're looking for cc's or even info about cc's. Moreover, the competition for credit card names is enormous, including the plural of this one, so the only thing it has going for it is that it's solidly brandable and a nice example of a "101" name.
That said, I'd be inclined to agree with the $500 to $1K range posted here and would even say $1K+, as long as you're willing to put in the expense of trying to develop something that could get the good SEO which this probably could get in time, instead of looking for something with more "natural" potential.