Does anyone know if vista 32/64 bit is compatible with quad core cpu's at this time?

if quad core CPU support 64 bit , it will.

but is quad core out yet? it will cost $1000.

Yes quad core is out.
The reason for the question is that an individual on the abit forums is complaining about the AW9D-Max m/b. He installed a quad core QX6700 CPU, and is unable to install any version of vista. It ran fine (vista) with a 965 cpu, but was unable to boot into vista with the quad core.

So he reformatted the drive, and tried to install rc1/rc2 and 64 but was unable to install any of them. I had him update the m/b bios from 12 to beta 13 to recognize the cpu, but he is still unable to install vista.
I realize that vista is still beta and may not support quad core at this time but because the m/b is advertized as being quad core and vista ready, he figures the m/b is at fault.

I was hoping to have an expanation as to why it would not install.

I'm not sure then. but I have PD 930 with asus mobo made beginning of the year, and I installed vista it did install fine. at that time, CPU and mobo manufactuers didn't even worry about vista ready.

I guess quad core is very new, there may be still issues with quad core CPU and mobo compatibility. And if you are running vista ultimate, you need a good graphics card and 2GB+ RAM.

He's also trying to use the nvidia gtx 8800 and 4 gigabytes of ram.