The recent wave of rumours coming from the inquirer looks like FUD, hopes and missing expert knowledge lead to signs for an AMD64 compatible desktop chip coming from Intel in a few months.
It surely won't happen. And even if it would be true - it won't hit AMD that hard since the performance differences of Opteron/AFX/A64 and P4/P4EE will become even better for AMD thanks to the fact that simple things like 64bit address calculations or 64bit integer arithmetic will just need a longer latency at 3.x GHz than at 2.x GHz.
And AMD will still have other advantages thanks to HT and the integrated memory controller.