I'm no expert on the trends of RAM, but its been going up since september (it bottomed out at around $29 for 256, then started going up)
Anyways, this is what I suspect.
During Christmas season the demand for RAM goes up, thus the supply goes down, and prices rise. After the christmas you should see prices drop a bit.
The other problem is a major company that was making ram just went out of business, they had their ram so cheap that other companies were forced to compete, wish I could remember the name!