Questions about AM3 and DDR3?

So basically I want to know whats the differences between both the AM2+ and AM3 socket as well as the DDR2 and DDR3 Memory. Also is it worth switching over to the newer tech even if you already have AM2+ Socket (that I'll put a Phenom II X4 940 on) and should I switch over from my current Corsair XMS2 DDR2 800Mhz?

I agree wiith cjl. AM3/DDR3 makes perfect sense for a new build, but not for an existing build that already has an AM2+ motherboard.

Performance really isn't that much different. As already mentioned, the AM3 HT link speed is faster (4000 MHz vs. 2600 MHz for AM2+). The AM3 processors generally have more L2 cache as well. In regards to RAM, DDR2 in general has slower refresh rates but lower latency as opposed to DDR3. When you do the math and work out all the timings of the latency and refreshes, DDR3 provides better performance overall. But again, if you already have AM2+, I would wait until a normal system rebuild to buy an AM3 motherboard and DDR3 RAM. You could purchase an AM3 CPU sooner, as they will work in virtually all AM2+ motherboards.

Thanks for adding; I should have made that clearer.