well, after finding this post figured... why not, I need a new one anyway.
I currently use keyclone and octopus.
Octopus, clunky for what I need does not work on macs (I have one for non-wow stuff) and will not work in conjunction with synergy.
Synergy, spins ya like a top in wow.

Well, I tried it, after figuring out that I actually need to install impulse on each machine and install multiplicity through that. :/
It works really well. Easy to set up, it says it has OS X support comming, which is great, and for now, it works seamlessly with synergy.

So I have it set up like this.

Slave Mp (XP No KB)<-> Master Mp (XP w/KB)<-> Slave Mp and Master Synergy (XP No KB)<-> Slave Synergy (OS X no KB)

This seems to work perfectly and to me, well worth the $15