As Alex points out, at least two of the reviews for these apps indicate that the apps were purchased against the buyer's will, with hacked iTunes account credentials. The ongoing MacRumors forum thread here indicates a possible spike in iTunes fraud, with major purchases being charged against unsuspecting users' accounts. Alex also notes that Apple's response team is already looking into the issue.
If you have unexpected charges on your iTunes account, be sure to notify your card issuer or bank immediately, and then send word to Apple. It may take a bit longer to get help during the long weekend.
Updates: 9to5Mac points out that the offending apps have been pulled from the store. Arnold Kim at MacRumors reminds us that compromised iTunes accounts have been reported for years, and it's not clear that the current circumstances represent a spike in malicious activity.