The larger problem though, becomes scalability. If you make the weight of higher level users votes count for even more XP, this increase compounded by the constantly growing number of total PerlMonks all voting more and more total votes everyday, it gets to the slippery slope point where a newbie signs up, makes a great post that gets moderated to the Monsastery Gates and gets so many votes so quickly that they climb several user levels in one day. If 31 high level monks voted a ++ on a post and each of those was worth 3 or 7 XP combined with say 127 normal votes (as there would be far more total users) and you have a first post leaping right onto the doorstep of the Monk user level. It's gotta scale well with many more users and votes and still be meaningful.
I think Shendal is right on above that we first need to evaluate what the XP system is supposed to designate (if not solely participation which includes voting). TTFN.
p.s. Initiate Nail Removal Immediately!