If you're not one of those types that has to have a new game the second the employees open the box in the store, GameStop's current StopWatch sale has an offer for you. If you pre-order Super Mario Galaxy within the next two days, you will qualify for free two day shipping. As someone who often can't get out to the store on launch days due to travelling or what have you, I have turned to online ordering for a lot of my purchases and free expedited shipping is always a bonus if you want your game in a semi-timely manner.
A couple other GS online offers include: $US 10 off any video game or accessory priced $US 29.99 or more with the purchase of Guitar Hero III, and free in game items for ordering Army of Two, Crysis Collector's Edition and Unreal Tournament III.
Free 2-Day Shipping on Super Mario Galaxy! [GameStop.com]