Most Helpful Girl
I think this is a personal decision. If you feel the need to delete the photos, then do so. However, I don't think it's necessary. Any guy who is turned off by you having a life before him isn't the right man for you.
He more than likely has his own past. Now whether he chooses to share that on Facebook is his own decision.
I don't think you need to worry about the pictures. If you feel they are special and hold good memories, then keep them up. It shows your personality and interests. Plus your ex was a major part of your life since you two dated for so long. This new guy has to accept that.