Got us too!
The prize was a digital camera for $1.50, which is clever because we weren't that excited about it, so forgot rather than sitting around waiting for it to come.
Four months later we realised we hadn't received it, so we trawled through the credit card details, and found the $1.50 charge, followed by four monthly charges of $89.99. At the time, we didn't even remember the name of the guys selling the camera, so it took us a few phone calls to connect the two. The only reason Ziinga stood out on our credit card statement was because it was the only name we didn't know!
Looking more, we found that an account had been automatically set up, with a random name ("pageuser125" kind of thing), a fake date of birth and so on.
The credit card's been cancelled, and a dispute's been opened. We'll wait and see how it turns out.
Ziinga seem pretty clever. To use a low value product to get you in, but not get you so interested that you actually care about getting what you paid for, so you don't bother checking! I think they deserve every penny they scam out of idiots like us!