I'd straight out have a tendency to disagree. I would assert that most of the price is driven by speculation - the rest is simply some small driving factors that have little influence whatsoever. While I have stated that increased infrastructure should lead to higher prices, there is no definite price region anyone can predict simply because the whole thing is too grey. Not to mention, what justifies a price at $640 where we are now and $700 or $500 in the future...

Even their 'factors' are simply just the infrastructure and supply and demand really.