Isla, like many famous women before her, is converting to Judaism before she marries Cohen. Great, except she's also in the middle of shooting the highly anticipated (well, by fashionistas and chic lit fans at least) Confessions of a Shopaholic and doesn't have the time to devote herself to her Torah studies.
Mama and Papa Cohen are said to be displeased by the turn of events, but it seems like Fisher is taking her conversion, her marriage, and her career quiet seriously. Instead of doing enough to get by, she wants to really immerse in her new faith without compromising her relationship or her job. To which we can only say, Mazel Tov.