Microsoft is planning to let Surface Laptop owners upgrade to Windows 10 Pro free of charge until the end of the year. While the laptop ships with Windows 10 S, a new version designed just for Windows Store apps, Microsoft isn't charging Surface Laptop owners the $49 fee to switch to Pro. If you purchase another Windows 10 S device then you'll still need to pay the $49 upgrade free, but Surface Laptop customers will have until the end of the year to switch.
Microsoft is also throwing in an Office 365 Personal account for a year with the Surface Laptop, providing full access to the desktop versions of Office. These apps will arrive in the Windows Store soon, and even the Windows 10 S shipping on the Surface Laptop will be able to run them.