I'm almost done with rewrites on a novel, getting ready to send it to agents. I noticed recently on Publishers Marketplace that another book (same genre) with the same working title just sold to a big house. I know titles are fluid and by the time it gets to print, the title on the PM book might have changed. Or if I sell my book, the title could change. My question is: should I come up with a new working title before sending it out, if only to avoid confusion from agents/editors who may have considered the PM book? ("Didn't I just see this?") I'm reluctant to do it, because it fits so well with the book, but I don't want someone to pass, thinking they've looked at it already.
Great question! A variation of this titling issue happens to a lot of people--you know, having the perfect title for your book and then realizing there are a host of outside circumstances working against your using that perfect title.
Honestly, as an editor, I remember stuff like that (if I've seen a book by the same title, I know instantly, even if the first submission was a project that went no further than my desk). I don't think I find repeat titles offputting per se, but I definitely remember. This is relevant in your case because since it's the same genre you might be submitting to the same editors.
That said, I got a book into production that had the same title (same genre, slightly similar plots) as another book at a much, much larger company. We had both announced our deals in PW, and just missed each other through neglect. At the last minute, the big house called me and tried to bully me into changing my title--but we were already close to press, and so we won (they had to change). There is no moral to this story, really; it only proves that it could come about that no one ever notices your title match.
But I think to be safe it would be a good exercise for you to think of a second-choice title and submit under that. Just in case someone is anal (and editors, as a career discipline, often are). Besides, as you point out yourself, retitling is something that often happens for marketing reasons, so if you've already spent some time thinking of second- and third-choice titles before you submit, you'll be prepared to have a great conversation about your options later.