MARBLEHEAD – As trick or treaters munch away at their Halloween treats this evening, they can look forward to something different in the town?s December holiday observance.The Marblehead Christmas tree lighting, which will kick off the town?s 41st annual Christmas Walk, will be moving from Abbot Hall to the new National Grand Bank parking lot on Pleasant Street.Marblehead Chamber of Commerce President Cindy Latham and Executive Director Ann Marie Casey gave the selectmen plenty of advance warning about their proposed changes when they visited the board last week.The tree lighting is scheduled to take place Friday, Dec. 2, at 7 p.m.Because the parking lot is adjacent to Memorial Park, which contains the town?s monuments to its war dead, Casey said the chamber will remind parents and children to respect the monument area.This year?s parade will be longer as well, proceeding all the way to Gerry Street, up the hill and back to the information booth so that marchers will pass the Village Plaza merchants and the Warwick building, which is under construction as the town?s next new commercial area.?It?s a great addition to the parade,” Casey said. “That area is being developed and this time next year there will be a retail presence there with a completely different look.”