If you're buying a new laptop and want to save some money don't load out on memory at the manufacturer's store.
Instead, skimp on the RAM and save at the checkout. Then, go to a place like Other World Computing, Kingston, NewEgg.com, Buy.com or Crucial.com to purchase the RAM you need. For example Apple sells their 4GB upgrade for the MacBook Pro for $700. At Other World Computing, you will see a compatible upgrade for as low as a $100. That's $600 of savings with guaranteed compatibility, as well as video instructions online for those unfamiliar with the memory upgrade process. Plus most manufacturers no longer dock your warranty for self upgrading system RAM.
So save yourself some cash on your next laptop purchase and don't upgrade your RAM at the manufacturer's store.