This would be useful for books which, for example, you DNF'd the first time you tried to read them, then came back for a second attempt and finished the book. I think it would also be cool if each separate read date could have a different star rating able to be assigned to it, too; maybe a book that you loved when you were younger didn't hit so well when reading it later, or a book that you had to read for school and marked accordingly was actually a work of genius when you're revisited it outside of a school setting, but you want to keep your original score for sentimental reasons, or to track your personal growth with it; the status/star rating that would show on your book would either be the most recent one, or be sorted as a "priority" (e.g., you finished the book the first time you read it, but you DNF'd the second time for whatever reason, be it life got in the way or you lost interest in your re-read, the "read" status takes priority in showing up over the "DNF" status).

(As a sidenote, it would be great if we could see these re-reads pop-up in the chronological timeline of you finishing books, i.e., they appear more than once on your "read" page, but have the different dates you finished reading them listed.)