The full changelog can be seen below:
Android 6.0 (Marshmallow)
Exercise greater control over app permissions
Experience enhanced battery-life through Doze
Redesigned App Drawer
If you’re a Rogers customer, own a Galaxy S6 or Galaxy S6 edge and would like to see if the update is ready for your handset, simply head into the following menus: Settings > About Device > Software Update > Update Now. Alternatively, you could always wait until you receive a push notification prompting you to install the upgrade, but this has proven to take slightly longer than manually scanning for it.