Developer DICE's Johan Andersson states that 2GB RAM for the next generation of consoles "won't be enough", and believes that they will need at least 4GB RAM - and recommends 8GB RAM.
"There's two things: memory and processing power," Andersson said in an interview. "We need lots and lots of processing power. The more you can cram into a machine, we'll take advantage of that."
"Two gigabytes would not be enough when it comes to RAM (random access memory.) Four gigabytes would work. Eight gigabytes? Yeah. I think that would be perfect when it comes to memory," he continued.
He then noted, "Presumably next-gen consoles will be rendering internally at 1080p, so they'll need much higher resolution assets than are commonly used for modern games (usually rendered at 720p and scaled up). Also, console lifespans have been getting longer, and presumably the next-gen units have an even longer journey ahead of them. More memory means more future-proofing. Finally, RAM is cheap. You can buy 8GB DDR3 modules for $40 retail. Buy the chips wholesale and it's easy to imagine the cost for 8GB dropping under $20."
Battlefield 3 requires a minimum of 4GB RAM to play on PC.