Well Intel's original plan was to keep x86 32 bit, forcing anyone that needed more into IA64. Fortunately AMD came out with x86-64, and when it was clear that

Well Intel's original plan was to keep x86 32 bit, forcing anyone that needed more into IA64. Fortunately AMD came out with x86-64, and when it was clear that IA64 wasn't going to be competitive, Intel brought x86-64 to their chips.