It as been determined there was no technical problem with the car, but the owner had an iPod, a mobile phone and a digital camera in the car. The iPod was on the front seat, and that is where the fire apparently started. The Saab was not even running when the fire broke out. It's not known if the iPod was charging, or just sitting there by itself.
The investigation is ongoing. We all know Apple makes some hot products, but this one may have been a little too hot.
Here's a link to the Google translation of the original Swedish article. We'll let you know if we hear more.