This chart appears to have been fairly accurate.  We are currently riding above the lower parabola and reaching toward the boundary of the upper parabola.
If the price of bitcoin continued a path in alignment with this chart, we would be looking at a lower bound price of at least $750-ish by January 1st of 2017.  The upper bound is harder to tell since the upper parabola is off the chart, but (again, if this chart trend holds), the upper bound would be $1500+ by the time the ball drops on new year's eve