When it comes to AP style, yes, book titles should be italicized. This follows the style set out from the Associated Press style guide, which dictates that book titles and other larger works such as newspapers should be italicized, with titles of smaller works such as individual chapters or articles being placed within quotation marks. The reasoning behind this is that italicizing the titles creates a visual difference between the titles and the other text, thus making it easier for the reader to identify what is being referred to. Additionally, it makes it easier to differentiate between the title of a larger work and the title of a work within that larger work.