Cadillac has released the above rendering of, well, mostly of a headlight, in advance of the Detroit Auto Show.

Eventually, Cadillac is expected to unveil an entire concept car connected to this headlight–once that car is built, that is. That as-yet-unnamed concept is expected (by us) to be a large sedan that will reveal the basic styling the brand's upcoming XTS full-size luxo-boat that will replace both the STS and DTS models. Last we heard, the production car will use a version of the Buick LaCrosse's Epsilon front-/all-wheel-drive platform and won't go into production until 2011.

We make this leap of establishment since, well, we know the XTS is coming, we can see two door handles on the driver's side (in spooky blue light) and because this thing looks big. Case closed.

We asked a Cadillac rep about the vehicle's size to which he cleverly replied, "no comment." We suppose it could be a concept to hint at the upcoming 3-series-fighting ATS sedan or possibly a thinly disguised Tata Nano competitor. He did confirm that it will not be a re-badged Toyota iQ city car.