Publicly offering to commit a felony for payment would be a very risky and pointless "prank", so I highly doubt it is. More likely a scam or ill-considered get-rich-quick scheme.
I believe parody is considered protected speech. Everything on that site is so absurd (the zany video, the lists of email addresses) that I find it hard to believe a reasonable person would consider this a serious offer to DDoS somebody. The more I think about it, the more clear it is that this is part of this company's "guerilla marketing" strategy.