There is an iPad app by a company called "Saitara Software" called AC-7 which basically emulates a Mackie control surface. It has modes for several software programs including Sony Vegas. The control in the different modes is the same, but the labels change to better represent what is going on in that particular program. Anyway, I have it configured and I can make it work with Propellerheads Reason, but not Sony Vegas. Has anyone got this working?

http://www.saitarasoftware.com/Site/AC-7_Core.html