What is the required level of quality for photographs submitted to a book publisher?

My friend is thinking of presenting the idea of a photographic book (coffee table / type of gift) to a publisher. He wants to collect a lot of pictures and assemble them into a presentation. His basic idea sounds good, but I fear that its camera quality is not enough. Is there anyone who knows how high the quality of these images should be? As there is a minimum number of mega pixels? His camera in the course is only 8 Mpx.TIA!
Categories: Quality Tags: Book, book publisher, camera quality, coffee gift, coffee table, High Quality, Images, Level, mpx, photographic book, photographs, presentation, publisher, Quality, required, submitted, What