I was excited about goldskin and due to the obvious oppurtunity it may have added so i bought one.
after testing it appears they put a hidden cooldown on the proc. I tried with slow weapons and weapons up to a 20%ias balanced dagger. I did tests on my monk and my barb using frenzy. I was unable to get it to proc more then about once every 10 seconds. the gold it drops is decent but even if the proc was limited to once on a specific mob every 10 seconds the max your going to obtain with a vampiric 4 pack seems to be in the neighborhood of 400k-600k an hour.
so in my analysis it can work but it doesn't some that great to be honest
has anyone else tested it and come up with different results if so i would be interested to hear them.