Car companies just love facelifting their current products. It is a much cheaper way to get a few more years out of the current product, because developing an all-new vehicle is very expensive.
Low volume car companies are even more likely to update current products rather than develop new ones, and Ferrari is no exception. In the past we have seen the Testarossa turn into the 512TR and then into the F512M. The 348 spawned the 355, while the 456 became the 456M. The 360 Modena gave way to the F430, and the 550 became the 575.
However, don't expect to see the replacement model for the 599 to be just an update. Reports suggest that its successor will be an all-new car. Ferrari recently replaced the 612 Scaglietti with the completely new FF, and would probably take the same route with the 599.
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Ferrari 599 Facelift Scrapped in Favor of All New Model on AutoGuide.com