The study of religion in history is on the rise according to a report issued by the AHA. Nearly 40% of AHA graduate students, assistant- and associate-professors surveyed indicated that religion was one of the three most important areas of their work. Most other areas of study in history showed a decline in importance since 1992, the first date that data were collected; only religion, African-American, and cultural history showed increases.
I am not aware of comparable data in other disciplines, but the extent to which religion may be part of academic study deserves our attention. Like psychology more generally, the psychology of religion has natural connections to disciplines across the academic spectrum, from biology to sociology. Of course, the role of religion in psychology itself has been an important area of interest to psychologists of religion, who often see religion's place in psychology as being under-appreciated. One good example of this is Michael Donahue's work documenting religion's neglect in social psychology. You can download his 2005 article on this subject, Disregarding (and disrespecting?) religion in social psychology: The case
of the 1998 Handbook of Social Psychology from his site. It makes for interesting reading, whether your focus is social psychology or another aspect of psychology.