i still have to compute the formula for upper and lower 95% confidence level
Lol, remember this depends entirely on your argument being sound. Think of the recent CDO pricing disaster.
Here's my 2 bitcents:
The influx of new users drives the exchange rate.
The exchange rate drives the mining power, with some delay.
For 2 Th/sec we currently need about 1MW electricity. With these costs, the system cannot grow on speculation alone, for very long.
When the user growth slows, current miners will slowly bring down the prices, even if no early adopters cash out.
From the demand side, there's still lots of growth potential.
$10/BTC is psychological resistance and we'll probably retest the lower single digits. If $20 is breached, we could see $100 at the end of the year.
Maybe Bitcoin really does become as big as PayPal, then these prices are justified, but imho the chances are overestimated.