The answer to the above question would appear to be "Yes". According to IESB.net, Jason Voorhees will wear both the potato sack and famous hockey mask over the course of the Friday the 13th reboot, set to release on February 13, 2009.
Producer Brad Fuller told IESB that the new film will condense the first three movies of the original series. I'm not sure if this means that Jason's mother Pamela will make an appearance at the beginning, but it does mean that Jason will start out his killing spree wearing the sack (from Part 2), and then transition to the mask (from Part 3) at a key moment in the film.
Rumor has it that the crucial mask-donning scene has been shot both from behind and from the front, and that the decision will be made during the editing process whether to show Jason's face.