From Multicore.info, a pointer to a talk by Jeff Bader, on the challenges of diverse choice in memory technology
Bader said that today’s memory situation parallels the history of TV. At first, your choice was simple: to get a TV or not; a few years later, it was just color or black and white; and now, what an array of choices. Similarly, in those old days, the memory-choice options were primarily size, voltage, and boot block configuration; now there’s NAND, NOR (in various flavors) and, coming on soon, phase change memory (PCM), ferroelectric RAM (FRAM), and magnetic RAM (MRAM). Add to this serial or parallel interface, package choices, and other options, and it’s a designer’s wonderland and also headache.