Infiniti unveiled its upcoming three-row JX crossover at the Pebble Beach Concours d’Elegance this week, joining Lexus and other prestige brands in leveraging this luxury event for introducing new models. Infiniti officials cite a key benefit to the JX is that its third-row seat is not a “penalty box.”

The JX is powered by a V6 engine teamed with the brand’s first continuously variable transmission. It will be offered in front- and all-wheel drive.

Among the convenience features, the JX will offer a 14-speaker Bose stereo, Infiniti Connection telematics system with automatic calendar synching and navigation integration to route to appointments, and the Infiniti Personal Assistant live concierge service.

On the safety front, the JX will offer blind-spot intervention and back-up collision systems, with cross-traffic awareness.

The production JX will be shown at the LA Auto Show in November, and Infiniti says it will provide more details at that time. The JX goes on sale in spring 2012.