@Flimzy Regarding meta: sounds good. That's the right place to settle the debate. Regarding the "site guideline": I never said questions about Mormonism were off-topic on this site, or that the site shouldn't consider them "Christian". I said they are a cult, per Caleb's explanation. (He would say, "Christian cult".)

@Jas3.1 I realize that Caleb's answer provides one (among many) definitions that labels Mormonism as a cult. Other definitions he mentions would also categorize Catholicism and Protestantism as a cults. This is the accuracy problem with the term.