I think we're going to have a sharp rise once big news comes out (say the eBay/PP thing) and that may create its own curve separate from what we've been dealing with. There are a lot of positive things in the works right now. I just think we may hit our short-term cap shorter than we think (ie. hitting 5k within a year and then being stuck there for a few years).
Near-term good news events like integrations of bitcoin into eBay / Paypal, assuming that sort of thing occurs (and I think it's inevitable), should not be considered outside or "separate" from the logistic model. They are just dominos lined up and waiting to fall, according to a model where each domino knocks down two more (yielding a doubling time of 90-100 days). And there are still a LOT of dominos left standing, more than anyone will reach within 2 years at the rate we're going.