Here's hoping that Uggla 2007 = Jorge Cantú 2006
As far as picking up Upton, it depends on what you need. If your team needs speed, I'd take Upton. If you are looking for a spot starter that won't kill you (i.e. good batting average, etc), I'd stick with Aurilia. If you are seriously worried about your current 2B situation, I'd say that Upton has more Upside.