This dude is a scammer.
I sent 4 euros to him via paypal, and he didnt gave me the key after that.
This is from his post on elitistjerks :
http://www.elitepvpers.com/forum/world-warcraft-trading/2069028-selling-mop-beta-keys-cheap-2.html#post18303083
This is our skype convo ...