For what its worth on the shaman forums now the is a post about how high LvB is crit for both self buffed and raid buffed. It seems like people are able to get anywhere from 10k to 14k from a single LvB and higher with raid buffs. People posting about getting 8.5k before the patch on single LvB. In this case x5 could be HUGE.

Oh and where is the bonus damage % from those talents applied?