Quite a few people have taken advantage of it, but less than you might think. It brings in some extra traffic, and the occasional new paying customer, so overall it does what it's supposed to.

For the most part, the people who request the Cheap Bastard Plan don't have much in the way of traffic, so it's not particularly expensive to service them. Every once in a while I'll get a request from somebody who's a bit "cheap"'er than normal, asking for an upgrade after posting a comment to an online forum or blog entry, or even just a tweet. But for the most part people tend to have nice things to say about the product, and proceed to say them.