AMD Athlon x2 vs AMD Athlon II x2. What is the difference? Does the "II" stand for second generation?

The Athlon X2 is a processor that even though it's been through a lot of changes, has managed to keep the same name. I believe they got their start back in 2005 when they were called the Athlon 64 X2 and used socket 939. There were even Athlon's before that, but they were single core. (???!!!!)
Anyways, like I said, the Athlon line has seen some changes. Different core speeds, core voltages, power usages, cache sizes and socket types. They were socket 939, then AM2, then AM2+, and now, in the current Athlon II X2 form, use socket AM3. The current models mostly have a 2MB L2 cache (with 1 or 2 exceptions of 1MB), compared to the older models that were up to 1MB. With a couple of 'e' model exceptions that draw 45W that were released last month, most of them use the same amount of power, 65W. Previous models used 35W, 45W, 89W, 95W, 110W and 125W.
Basically, the main differences between the Athlon X2 and the Athlon II X2 are the larger cache and different socket type, AM3.