I will buy an x86 powered Mac
I do think Apple's switch to x86 has great potential, running standard components and processors, and with UNIX security, the MacOS will be a great substitute for Windows.
I believe Apple is going to support AMD64 eventually. However, even if it is an INTEL box, I will buy one just to try it out, as long as it does not use the dreaded 200 watt Pentium 4.
Microsoft better run for its money.