These guys are trying to promote their business or rather inflate their feedback in exchange for a free puzzle. Even though it says $.99, it's Free with Free shipping as per the description.
Via Whirlpool Freebies Thread
http://forums.whirlpool.net.au/forum-replies.cfm?t=984520&p=…
EDIT: All gone!
Look at one of the terms:
Positive feedback MUST be left immediately
They require you to leave feedback before they ship it. So even if they don't send it after all, I guess you wouldn't be bothered to file claims, so they might get thousands of free feedbacks!