I agree that the RAM price is literally up 100%. I used to pay $40 for 4GB kit in average, but now is exactly $80 in average.
There seems to be 3 reasons:
1) USDollar is losing the value. FRB printed too much dollar bills to buy US debt that Treasury Deprartment needed. Yes, you heard right. They just printed money to return their debt. Of course, the dollar will lose value. One dollar used to worth 120 Japanese Yen before summer, but now it worths only $90. I'm sure the rate will be worth against other Asian countries wherever developing quickly.
2) People are upgrading their system to move newer PC with more memory. Win7 was released and people with XP would move to Vista, Vista user will move to Win7. Some move from 32bit to 64bit system which can use more than 4GB of RAM, resulting for buying more RAMs, more demand.
3) The Manufacturer's/Wholesaler's excess inventory adjustment is now over. Due to the recession, they were trying to clear the excess of inventory to be more light weight by reducing the inventory level. That phase is over now. So, they don't have to do any bargain or "mail in rebate" campaign any longer.
I'm a system builder, and this price change hurts...