You're right! The ones that were going through already had www. on them. My husband, a programmer, said Family Search is now forcing proper URL formatting. There could be several reasons for that. They may have added servers or had bandwidth issues. It could be any number of things. Using that formatting is actually best practice. It could even speed up searches. They probably won't change this. I just wish they would have let people know they were doing it!
To make matters more confusing some of the links have hidden the www. but it's there even if you can't see it. Those links work.