Meaning of "all-new" in advertising-speak

Sometimes hyphenated, sometimes not. Most commonly heard in car commercials, eg "Introducing the all-new 2010 Cadillac SRX Crossover". I've only heard it since moving to the US so perhaps it is a North American thing.

Does the "all" actually convey any specific meaning? Am I losing anything by interpreting "the all-new 2010 model" as "the 2010 model"?

The phrase "all-new" in advertising simply emphasizes that the product is completely new. It is not simply a new name or small iteration from the previous model — everything about it is new, so it must really be worth buying!

(Naturally, in the world of advertising, what they say is prone to extreme exaggeration!)

Yes, "all-new" does convey a specific meaning, and the specific meaning is this:

"We want you to buy one and will say anything to try to convince you to do so."

I respectfully disagree with Kosmonaut to the extent that I believe "all-new" doesn't really mean the car is totally redone. It may not even mean it is mostly redone. It may only mean they have put a new name on an old product, with possibly a few cosmetic changes.

Really, advertising-speak is such an ocean of waffle-words that you can't take anything from it to reliably mean anything at all. And I say that as someone who wrote advertising copy before I found a better life. The art of writing such copy is to make the reader think the words mean much more than they do.

There is a unique phenomenon that occurs in the auto industry. Any particular model (e.g. a Toyota Camry) undergoes significant redesign every five to ten years. In other years, the changes from one model year to the next are very small.

Frequently when a car model is described as "all-new", that is referring to a major engineering refresh/redesign, as opposed to minor year-to-year changes.

I think Robusto is really onto the nub here. "All-new" is virtually meaningless. The description is attached to any product as a way of garnering attention. Consumers are known to prefer things that are new. New things are exciting. Old things are boring. You already have old things, so why would you want to buy another old thing? If something is new, it is appealing. That's why advertisers use the expression "all new".