That is your Clutch housing cover. There is an O-Ring on that as well. Do you have all those bolts? And are they all tight? If you have the time, I would take it back to the shop and tell them to check it out. I mean, it is probably a seal, which is an easy fix, but they should do it for free, and I would make sure they know to CLEAN the bike afterwards, and get all the oil residue off.
2008 700xx; Power Bomb header with power core 4 exhaust, Power Programmer III, pro armor nerfs, prm products control front and rear bumpers and full skid, 10" ITP rears, ITP Baja's fronts, RZR 2's all the way around, Uni filter, 13t sprocket, CCP steering Damper, DS450 shock swap, Dual Gasser Throttle, bar risers and Moose barkBusters. 730XX kit plus other engine mods!