It's Not About the Language, Stupid
A great developer isn't the one with the deepest knowledge of their language of choice. Most of the time (and there are exceptions when you need the deployment demon or the garbage collection guru) the best developer is the one that has the best understanding of all of the pieces of creating great software. That's why approaches like Domain Driven Design are so valuable and why project management approaches like Scrum and engineering practices as described in XP are so crucial.
It's why I'm particularly excited to see that Lean software pioneers Mary and Tom Poppendieck will be giving a presentation in NYC next week. If you're interested in the craft of software and would like to meet like minded people from different language communities, I think these kind of meetings are an amazing opportunity to become a better developer - irrespective of the language you happen to develop in.
Comment on the previous posting if yu can make the meeting in NYC next week. I think it's going to be a memorable event.
If they talk around the same topics I'd definitely recommend it for anyone in software, especially team-leads and managers or anyone else trying to manage a continuous software development process.