I come back to eco-system development. MUCH more going on now, including global geo-political awareness, etc, VCs are getting their feet wet, infrastructure is being built out, we've got some bitcoin hedge funds, better security, (mostly) well understood best-practices for handling bitcoin as both a user and a business....
None of that was true in 2011. There was very little infrastructure base. The price was driven by the (in my opinion) correct analysis of bitcoin's phenomenal theoretical potential, but the ecosystem was incredibly thin. Yes, it's still absolutely in infancy now, but still amounts to much more of a solid core to support it in terms of mindshare, commitment, people, money, and services.
I'm maintaining a couple email chains about bitcoin now with dozens of people ranging from 20-something developers, to experienced VCs and entrepreneurs, to Wall St bankers. The level of serious, thoughtful, attention given to bitcoin now by a wider swath of people is great, and not to be under-appreciated.
+1