The Cadillac DTS limousine that George W. Bush will be riding in during the Presidential Inaugural Parade on Thursday will generate lots of publicity for the brand, but only a suggestion of what the production vehicle will be like. Cadillac fans will have to wait a couple more weeks to see the production DTS and several months to buy one, but the inaugural limousine has similar design cues in the front and rear ends, grille, head and tail lamps. The security and communications systems equipped in the car make it considerably longer, wider and taller than the production model. For...