the only thing that will drive the price back up is if the demand goes up.
right now ram isn't in very high demand since most people are content with 128-256.
Its very rare for the same computer product to become more expensive. This of course excludes retailers slashing prices due to inventory or other factors. I'm speaking from a strictly manufacturer/OEM point of view.
My prediction? DDR will remain at a cheap price. When PC2400 DDR comes out you won't see a big price difference...$15 at the most. DDR333 will raise the bar quite a bit, but you won't see a price more than $100 for 256MB. The main reason is that while the ram is faster and uses a faster FSB, to most users 512 of PC2100/2400 will perform better than 256 of DDR333.
The real thing that will drive the prices sky high will be a change in manufacturing or a completely different ram design (Rambus is an example). As far as manufacturing goes, DDR is not all that different from SDR. Until some new ram with a special manufacturing process comes out, the prices will stay fairly low.
This is all speculation so don't flame me if you spent years in college studying economics and feel the urge to make me look stupid
