Looks like moonkin should be getting 30% of their spirit value as spellpower, according to the MMO-champion patch note update for 3.1.2.
I saw that GC was thinking about putting it in, but looks like they managed to get it into a recent version of the patch. It really only buffs PvE moonkin, since PvP moonkin don’t have spirit, anyway. However, it makes the T8 gear for moonkin suck less than it does now (note how it’s still not good, it’s just not as bad, lol). We’re stuck with the current T8 gear, it’s not going to change. Lets just hope T9 gets better.
Also, it appears that Furor isn’t designed to really be useful in PvP. Ghostcrawler further explained Furor & moonkin here.
Furor appears to be working as intended.
It’s always been a problem with shifting & effects that only influence your stats in one form. Who remembers when shifting in and out of bear used to cause you to LOSE health to the point where you could shift-suicide? Basically, they made the intellect effect from Furor work the only way they can get that stuff to work: By just increasing your maximum mana without increasing (or decreasing) your current mana.
The way that Furor works, it’s probably not worth picking up for arena PvP moonkin. Some of the innervate buff is to help fix the problems that moonkin are having with mana in PvP. The entire balance tree probably needs a revamp (as in ‘wait an expansion’) before it will really be a viable PvP tree.