Areas of research that are subsummed within biomathematics or are closely related to it (along with random - Google links to more info) are ...
Dick Gordon (Univ. of Manitoba) has prepared two essays, one describing careers and opportunities in theoretical biology and the other explaining the advantages of having a physicist's perspective on biology. Also note that some people make a distinction between theoretical biology, mathematical biology, computational biology etc.; Prof. Gordon stresses the "theoretical" aspect of the approach.
There is a (now defunct) Canadian Society of Theoretical Biology (transformed into the Cyber Society of Theoretical Biology) and a Society of Mathematical Biology to promote the study of Biomathematics and Theoretical Biology and to promote communication between people with similar interests.
Science magazine (vol 272: July 1996) ran a "new niches" article on bioinformatics. This collection of stories was taken from their web pages.
McMaster Faculty members involved in some aspects of Biomathematics