I'm a java programmer with around one and half years experience. Recently my boss wants me to develop an excel add-in with VB.NET in next a few months or maybe I have to be fully in charge of this add-in in the further. It makes me quite nervous right now because I am really not sure what this VB.NET development experience could mean to me in the further as I am not so sure if it's good to diverse my experience in current stage. Any one could give some helps and suggestions?