CompUSA lost litiagtion filed against it on behalf of the public at large by the FTC. The suit demanded that CompUSA honor it's rebates. (They are notoriusly bad for taking 3-5 months to never)
CompUSA loses rebate battle
CompUSA often offers hard drives, memory, and wireless deals that are Mac compatible.
The average CompUSA rebate takes about 16-18 weeks. The average is 6-8 weeks for other stores.
See FixYourThinking previous article about rebates titled: Should It Be Spelled Rebate or Rebait?