Ultimately, it means that you'll need to purchase insurance for damage or loss when you buy from DigitalRev. It is legalese to inform you that title to the merchandise passes onto the buyer when the seller drops it off with the carrier. If something happens in transit and the item is damaged or lost, DigitalRev is not liable. You'll have to take it up with the carrier and prove it was their fault.
On the other hand, if it was a destination contract, the seller assumes responsibility and will fight the carrier if the package is lost or damaged.
There are other legal nuances. Just save yourself a lot of hassle and make sure you can get insurance on the purchase. Most of the time, companies will help the seller make claims like this as it would hurt their business otherwise. People generally don't understand contract terms, so they could walk away from the experience with a bad taste in their mouth about the seller. However, if the claim is complicated and difficult, the seller under a shipment contract could legally walk away.
Loss is pretty straight-forward. However if damage is the issue, the seller is still responsible if it can be determined that the damage cannot be attributable to the carrier (e.g., if a lens is found to have scratches to the body, but there is no external damage to the box it had arrived in).