I have to say that so far, I'm really happy that I have not paid for a Cha-Ching license. My initial impression of the application was that it was basically a toy, and of no use to grown-ups who want to manage their household's finances. I have since been set straight by a few people whose opinions I respect, and wanted to properly evaluate the application alongside my current personal finance manager of choice, iBank (which is, since the Cha-Ching price hike, about the same price).
You lot are fortunate to have received such prompt and courteous support. My experience so far has been, unfortunately, like wph's; in the past two weeks, I've sent my polite request with all the necessary info three times (to the address posted in this thread: support at chachingapp dot com, also the address it has been stated was posted to Midnight Apps' blog), and haven't even received an auto-response in acknowledgement of receipt. Rather discouraging, and not really incentive to fork over any more cash.