The Coupons & Discounts module should be enabled during the install with some discounts and coupons enabled.
Discounts have been added (available under "Store settings").
The coupons part (commerce_coupons 7.x-2.x) is still missing, as are the sample discounts / coupons.
Let's focus on the Discounts features here.
For now, the Discounts features are pretty simple. We should have a way to apply a discount per product type, per category...
The ability to just do Products -> Manage Products -> Assign Discount to selected Variations is sorely missed in the discount module...
Any alternative other than using taxonomy to assign discounts via tags?
Nothing more to be done here.
Drupal is a registered trademark of Dries Buytaert.