Sometimes they have site glitches and maybe something went wrong with trying to mark down the freebie so instead of being $0.00 the listing that's still findable via Google cache or from the linkage at the DCC catalogue page just doesn't show up at all any more until someone over there notices and manually fixes it.
Anyway, this has happened before in the past with a few DCC and other publishers' titles, and the usual pattern is that it got resolved and showed up again within the freebie period, so I'm feeling optimistic.
