It seems Samsung just hit a first today. They've announced their 2-gigabit or 256MB DDR3 RAM chip, which is the first to be mass produced using their 40-nanometer process.
The great thing about this process is that it allows the company to mass produce very dense chips without upping their power consumption. This keeps costs down as well. The idea here is to offer up 4GB RAM for notebooks and 16GB RAM for servers.
These new chips contain twice as much bandwidth as the old 1 gigabit chips. We don't know at this time how much the RAM will cost or when it will be made available, but you can count on these chips being available pre-installed in computer offerings first.