A mate of mine got screwed on ebay by someone with loads of feedback. Turned out it was a hacked account.

Nah, these seem ok - the Canada one takes cards directly as well as PayPal, and they seem to be camera-type shops.

The hacked accounts are usually obvious if you know the scam - the seller has been selling beany babies for ages and then suddenly lists projectors and plasmas with payment to Ukraine by Western Union. Every now and then I do a search for "plasma" and report the inevitable dozen or so hacked accounts. There is another dozen or so listings by people with zero feedback - this is almost certainly an account created with a stolen card but it is impossible for a user to report such an account. eBay could easily stop this by forcing people to confirm their card in the same way that PayPal does.

Gareth