HYUNDAI’S EVER-POPULAR Sonata sedan is due for an all-new replacement next year, and word on the wire is that Hyundai is prepping the next-gen Sonata for a global debut at the 2010 North American International Auto Show in Detroit next January.

Hyundai is expected to reinvent the Sonata as a four-door coupe, with a low, swooping roofline that stretches almost to the rear of the car. Several prototypes have already been spotted running around the Middle East during hot weather testing, however the entire car has yet to be seen fully unmasked.

Powertrain options are still unknown, however Hyundai will likely fit the 2011 Sonata with a newly-developed direct-injected petrol motor. A upper-spec V6 is also likely, and Hyundai has also stated that the new Sonata line-up will feature the Korean company’s first mass-market hybrid vehicle.

More details will likely be revealed in the lead up to the new Sonata’s unveiling at the 2010 Detroit auto show.