I work in automotive advertising. Have worked on several national accounts at large agencies (major manufacturers like Mercedes-Benz, Lexus, Infiniti, now Hyundai). Not cheesy little ads, we're talking TV and magazine ads. These are $300+ million accounts.
For our shoots, we use various prep companies to make the cars "camera ready."
I've got to tell you, most every prep company vendor I have uses Lemon Fresh pledge to some degree. Mostly for black plastics (incluiding tires, underhood components), and many use it for interior plastics of all colors as well.
I've been using it for some time now on my truck. The real attraction for me is that it repels dust and is cheap. Plus, it gives you a good-looking black that is not shiny. That "wet look" doesn't shoot well, and I don't like it at any rate.
However, most auto-specific products tout some sort of UV/environmental protection, and I don't think you get that with Pledge. But my car isn't parked in the sun too much (mostly just in the summer at the river), and is almost always garaged, so this doesn't really matter to me.