SAA will not be the first airline to receive B737-800s equipped with winglets, even though they were the first to order them. The first in-service B738 with winglets will be one of Hapag-Lloyd's new orders for delivery early next year. This aircraft will also serve as the testbed for the certification process. Hapag-Lloyd was the third airline to order the winglets, after SAA and ATA.
All SAA's B738s are receiving the wing mod's required for the winglets in the meantime, so that when certification is obtained for the winglets later this year they can simply be bolted on.
American has also expressed an interest in the winglets, but their already-delivered aircraft will require the wing mod's before the winglets can be fitted.