As the holiday shopping season draws to a close, consumers are keeping a tight grip on their purse strings, according to a new survey by the Consumer Business Practice of Deloitte & Touche LLP with BIGresearch LLC. More than 7000 consumers responded to the survey conducted between Dec. 7 and 13, 2001. It is the fourth survey in a series initiated in September, which confirms that during the past three months, consumers have not changed their holiday spending plans.Despite heavy promotions b...