No no, you've got it all wrong. Bitcoins will become popular as soon as hipsters become aware of it's existence. Right now, most hipsters aren't aware of bitcoins - the news feeds on their latest iGadget doesn't usually run stories on bitcoins. And they don't read "mainstream" techie sites like /. - they prefer to get their news from their local independent free magazines, and from carrier pigeons (which don't run stories on bitcoins).
But eventually one will hear about it, and when they do - they'll start foaming at the mouth and jump on that currency in a heartbeat! "Oh you still use dollar bills to buy things brah? That's so 2011. I only deal with BitCoins now. Yeah you've probably never heard of it - it's a pretty obscure currency - it's like, an only online currency dude. There's only a few places that actually accept them as a valid currency." And as he's telling his hipster friends at the local dive bar, sipping his locally brewed IPA (that his friends had to buy him, because the bar doesn't accept BitCoins yet) - his buddies will jump on the BitCoin bandwagon (but hopefully before it gets too mainstream) and hipsters will cash in on bitcoins like wildfire.
Now of course, retailers will realize this soon enough and realize they're sitting on a gold mine! All these hipsters will have bitcoins with nowhere to spend them, so every independent brewery, vintage clothing store, horn-rimmed eyeglass shop, pipe & tobacco company, scarf retailer and unsigned recording artist will immediately start accepting bit coins as a form of payment. And before we know it, bitcoins are mainstream and will be used everywhere. The only real losers here will be the hipsters after a year or two, who will be eventually disappointed when they realize bitcoins are totally mainstream now.