Without question, this is the future of real music. I'll link directly to the article on New York Times that talks about how Arcade Fire are benefiting from social media and the shrinking costs of production.
It is not just a growing trend - it's a paradigm shift (ahh, the favourite term of the bubble). Seriously though, deliver great music, use social networking (pitchforkmedia.com, myspace, etc), and put on great live shows!
Oh - and we need the masses to stop listening to crap music that the major labels turned out - but don't bet on it. Hold on - Nelly Furtado just came on - I love this song! :)