Your laptop is equipped with Intel Core i7-720QM processor (Arrandale series). According to it's specification on
http://ark.intel.com/products/49024 It can recognize maximum 8 Gb DDR3 1066\1333 MHz RAM. For comparison, Arrandale Core i5 processors are able to recognize 8 Gb of DDR3 800/1066 MHz RAM. Even Sandy Bridge Core i5 and Core i7 processors can use only 8 Gb DDR3 1066/1333 MHz RAM (ark.intel.com), so your expectations definitely pass ahead the time. If you want to buy a laptop with 16 Gb RAM support you need to wait at least for a year or assemble a desktop to yourself (some new desktop motherboards support up to 64 Gb RAM).
P.S. Some modern Sandy Bridge laptops have 16 Gb of RAM (4 slots for 4 GB). It's still secret for me how do they manage to bypass to the max memory limit of CPU, but it's obvious that four 4 Gb RAM blocks is not the same as two 8 Gb RAM blocks (integrated into CPU dual-channel memory controller can't recognize more than 4 Gb for each memory channel, so why it sees only 4 Gb from each RAM block and total amount of available memory is 8 Gb from 16).