I appreciate the effort but without more information this chart is of dubious value. What is the trendline based on? Unless it's based on stats and/or financial indicators then there's just too much room for curve-fitting and, effectively, useless.
There is no magic. The chart is average daily mtgox values, presented on a log chart with a least squares straight line (exponential, of course). Obviously the future is hypothetical, but this is the best fit projection using
known data.
That's exactly the case: it is a regression line, using known data. The current value vs. regression line simply means, the price is sitting at the line. No more, no less. It could mean the price might turn up again.
HOWEVER, it does not mean in ANY way:
* that prices can't fall any further (after which they might start rising again)
* nor that prices might also have already topped at their all-time-high.
There is just no way of telling, not even with your regression line.
Implicating anything else would be an insult to the science of Statistics.
Bottom line: a regression line is of no practical prospective use, it is for historical (ex post) analysis.
Understanding what you have said here is worth noting, and I do not disagree, and to explain the clarity of this:
The regression line shows the perspective on the known data, and the conclusion that can be made is phrased like this:
Given that the current data is showing a logarithmic progression and that we lay the regression line to it, the price currently is above or below the regression line at this moment and is subjectively under or over priced relative to the historical data.
Speaking of the prospects of the system, the price is without a known probability to follow this historical perspective.
TLDR: History gives insight future but does not predict it.