"Do you think the book cover is “dead”? Do you care whether the “covers” on digital books exist or not?"
I love book covers.
I could sit for hours on Amazon, Goodreads, etc. just looking at the covers of books. If the cover doesn't grab me, most times I'll skip right over it. It would take an awesome review or blurb to get me to read a book with a cover I didn't like.
Even with digital books, the cover is the first thing a person would see. Either when purchase/downloading the book or opening their ereader and selecting which book to read. It is what sets it apart from all the other books on your ereader.
Cover art stimulates my mind in either a negative or positive manner. I DO NOT like digital books that have a plain text cover. I will pass right over it.