I The only "revealing" thing might be the presence of a new device. Apple has occasionally let references of unreleased product IDs show up in its codes, but nothing that really described in detail what the capabilities of those devices were.
No they have been follow-on product IDs. Those really reveal nothing because an "next version" of the products are always coming along. You think Apple is going to jump up and say no more iPhone and iPods next year??? Those IDs are easily predictable in advance.
An ID for a new line of product would be information. The product line name is going to be part of the id. As badly a kept secret this is... something that confirms as brand new product line : Slate1,0 , Newton5,0 , or whatever would remove all doubt and spoil a bit of the "Ta-Da!" factor. The name is going a part of the grand revealing.