I can tell you, as a person who actually worked in the art department at Newsweek, they will NEVER change the content of an image, unless it's clear that the image is a photo-collage or an illustration. They will do a lot of retouching to make sure the image prints well, but in no way will they change the content.
I think it's safe to assume that there will be a firmware update. However, I don't think it'll be anything radical (like wireless). Otherwise, it'd be evident in the cover image or in the article.
What we've learned from all this:
1. New click-wheel a la the Mini. I don't know why some people think it'll be backlighted, but from the cover image, it just looks like a silver wheel as in the silver mini.
2. New menu items --> new firmware. As others have speculated the "Music" menu item seem to suggest that the new iPod might handle other medial, e.g. photos, in addition to music.
3. The 60 gig Toshiba drives are supposed to go into production in July/August so it seems likely that Apple will up the top end to 60 gigs.
4. No wireless. This is just a guess on my part, but if Apple put in something as radical was wireless, it'd be called out on the cover or in the article.