It's hard to tell much from the photos of the heavily disguised development vehicle, but it is expected to carry the same sort of notchback profile as the current version. Styling is suggested to carry over the "Born From Jets" theme more emphatically than the current model. Either way, it is widely believed that this is the same chassis that underpins the Opel Insignia.
Underneath the hood, we're expecting the current crop of gasoline and diesel engines to carry over, with the possible addition of the 2.8-liter V6 from fellow General Motors premium brand Cadillac. Sources suggest the new 9-5 could be ready for debut at the Frankfurt Motor Show later this year in September, so stay tuned. Thanks to Dan for the tip!
[Source: L'Auto Journal via Trollhattan Saab]