Inevitably this short term trend will correct and reverse and then people will suddenly find themselves holding more bitcoins that they thought they needed which will fuel a spending/exchanging circle until we find a bottom and repeat the whole pendulum swinging cycle.
The reason this is so hard to picture is because many people falsely think there is a such a thing as an equilibrium.
The reality is an equilibrium is purely theoretical and in practice the market is constantly readjusting. Currently the market is readjusting to a rising exchange rate, which if the demand keeps up might rise for a while longer but there will come a point when we run out of people wanting bitcoins, remember people can't eat them, or wear them, pr live in them and there is a finite number of people, so yes there's a limit to the demand and when we get to it the trend will reverse and the market will continue to correct except now it will correct in the opposite direction where even the correction itself will become a contributing factor to the correction until again people realize they could use some more bitcoins instead of other stuff where the market will again correct. And this will go on and on and on for ever, because there is no equilibrium.
Nice long ramble, but honestly right now, no one knows what the hell bitcoins are. News is spreading like wildfire and new people are coming every day.
Its about supply and demand.
Right now the supply is there, but the demand isn't.
The price is still going up up and away.
Once people actually find out what bitcoins are, there will be a demand, its a sloooooooooooooow process.. Right now slowly more people are finding out and more merchants are accepting.