My cofounders were C# guys. One new benefit I thought of recently was that C# is similar to Java and thats what mobile apps are coded apart from Objective-C. Who says the MVP has to be a webapp? :)

In anycase, my thinking was just get started first. Im probably going to dabble in Python or Ruby (probably Python) just to see what its like at some point. But for the time being, just getting my head down and writing code and asking really n00b questions on stackoverflow is definitely the way to go.