[jacquesm]

The community around Java is mindbogglingly large. That community was bought-and-paid for rather than grown organically but there are more ways than one to skin a cat.

The lisp eco-system is more like a collection of communities of very small (individuals?) sub-communities.

What technology underpins the web-app here has very little to do with the success of the community interacting here, though for sure there are many more lisp capable programmers here than on most other programmer hang-outs (lambda the ultimate excepted).