If your going to be gaming, don't bother with the CPU upgrade, instead upgrade your GPU. Upgrading your mobo is a good idea though, if you add a CPU cooler, you will be able to overclock your x6.
I personally would keep it the way it is. That 6 core phenom is nice! And you have a mini-ITX motherboard so you could do a compact build with something like a prodigy case. What cooler do you have for your CPU? I'd look into a watercooler and do some nice overclocks. I would keep it. Save your money and wait 3 or 4 years when something really bigger and better comes out,