I added a new label to my list - "young adult." I resisted using this label before, because I think that a lot of works that are considered to be for young adults can also appeal to adults, and vice versa. However, I decided that this label would be useful to me in the future, especially if I end up either getting a job as a teen librarian (here's hoping that interview works out) or if I get more interviews in the future for teen librarian positions. I won't give any anime or manga titles the "young adult" label - there are lots of libraries out there that classify all manga and anime as being intended for young adults, something I don't necessarily agree with, but I also think it's really difficult determining which titles are clearly for young adults and which are not.
Basically, if a book I've read was shelved in the young adult section at my public library, I'll consider it a young adult book. As for anime and manga, I've already got labels for those, so I think it's best to just use those and not worry about whether they're young adult materials or not.