New Pentium 4 Prescott processors with EM64T can also be expected on Monday, though these will not initially be available for normal users.
Information about the Pentium 4 Prescotts with EM64T was found at one of HP's Product pages. Probably they will be delivered this processor to some OEM's, like HP. X-bit Labs wrote this some time ago:
Intel said it would ship Prescott processors with 64-bit capability for 1P applications only to system integrators requesting such microprocessors for their servers and workstations. Although all Prescott CPUs, including Intel Pentium 4 and Celeron, are 64-bit from micro-architectural standpoint, processors supplying for retail channels as well as for typical desktops will have their 64-bit capability disabled.Prices are unavailable yet, but probably these won't be more expensive than the regular Pentium 4 models.
However, some sources doubt that it will be absolutely impossible for end-users and hardware enthusiasts to get Intel’s 64-bit Pentium 4 chips. They suggest that there will be some of such microprocessors supplied as OEM parts and reaching the channel.
Source: Tweakers