On NewEgg they list Opterion CPU's as HT:1000 and X2 CPU's as HT:2000
What exactly does that mean? It's my understand that Opteron and X2's are pretty much interchangeable, how, if at all, does this affect operation and interchangeabilty?
They are both 1000mhz. Sometimes it is written as 2000mhz because it is full duplex, but it is really 1000mhz. Just ignore it. Some people (even in stickies) say it's like ratting DDR, but it not at all the same thing.