I'm also not interested in learning yet ANOTHER language/framework now. I'd like to work on something in a larger group that will overlap at least a little with my current work.
Learning a new language to me would be just that; starting a NEW project. Instead, I'd like to take something I know well and learn to do even more with it. That to me would be an educational effort well spent.
In that vein I feel that working with other devs who code at my level on a collaborative goal would be something I have yet to experience and that I think I could learn alot from.
I think it's critical for developers to continually learn new technologies as they arise. This helps you stay sharp and remain competitive in the marketplace (whether you are an employer or an employee....)
If you just stick to the same framework all the time, you're going to find yourself out of touch with the modern programming world pretty quickly (again, either as an employer or an employee.)