From the offficial Press Release:

The Maserati GranCabrio, the first four-seater convertible in the Trident carmaker’s history, will make its world wide debut on September 15 at the upcoming Frankfurt Motor Show.  The introduction of the GranCabrio – the Trident’s third prong – completes Maserati’s product line-up that now consists of three different families of models: Quattroporte, GranTurismo, GranCabrio.

The GranCabrio was designed by Pininfarina and is continuing the Maserati tradition in open-top automobiles, beginning with the 1950 A6G Frua Spyder.

The GranCabrio is powered by a 4.7 liter V8, 323 kW engine and is the convertible with the longest wheelbase on the market.  The GranCabrio’s roof is strictly canvas-made, emphasizing the link with the Maserati tradition.

The Maserati GranCabrio will be marketed this coming winter, and experienced by customers the world over from the following spring.

(Source: Maserati)