I also have been hit recently by this person.
Sadly, I don't know if I will use bitcoinmarket again in the future, for any trades. It's just not trader friendly at the moment, there's no real limitations sellers can set on buyers other than price and currency. And the inability to change feedback is a real pita.
When this transaction when through, the buyer had over 10 positive feedback, so even if i could review buyer stats before going through with a transaction, i probably would have approved it on rating alone.
I have submitted email to PayPal and screenshots of all transaction information as my proof that i in fact sent the goods in question, which is just a silly requirement to refute my case since goods received isnt even the dispute, its unauthorized transaction. I will also be closing my paypal after this incident too. I dont think i should be held personally responsible for someone elses weak passwords.