I'm in the process of buying a MBP via Craigslist. The MBP is listed as new, in unopened box. The seller doesn't know if the screen is glossy or matte---apparently there is no indication on the outside of the box. The seller provided me with the serial number, but I wasn't able to use the serial # to determine the screen type. Does anyone know how I can determine whether the screen is glossy or matte prior to purchasing the MBP?