It's interesting that people see multiple dispatch as some esoteric computer science-y thing. In reality, it's just a way of organising code and complexity, just like object orientation is – and it has some compelling advantages over OO as well. For me, it's one of the killer features that I really miss in other languages, and it's well worth taking the time to understand it.
It would be great to see people doing more web stuff in Julia, but for the foreseeable future there will be some important caveats. The web libraries (including in Base) just aren't that fleshed out or battle-tested right now, and there's no Google-scale engineering effort making sure that the runtime is reliable over thousands of CPU hours. Whoever dives into that first will have to have a clear sense of the long-term value.