If learning a simple, conceptually mainstream language such as Ruby is too high a price to pay to get away from the madness of Ant and Maven, as it seems to be for some people commenting on Raven, I'm inclined to think you are in the wrong line of work. And Ant and Maven are hardly zero learning curve tools just because the syntax uses XML.

It's possible that Raven (or JRake) isn't the right solution, but the irrational fear evident, for example, in this TheServerSide thread, would be hard to believe if it wasn't just business as usual in the Java world.