I thought there were some important distinctions and clarifications about Mormonism from Ed Stetzer's blog.
Though the Mormons may use similar terms as evangelicals and Protestants when it comes to God, Jesus Christ, and salvation, the understanding of each of those terms differs greatly from historic, Christian teaching...It's not a denomination but it's a different religion.
In the following statement and in the video clip below, Stetzer and Dr. Tal Davis discuss throwing around the "cult" word.
A cult is often understood as a religious group with strange beliefs outside of the cultural mainstream. What you call Mormons today is what the world is going to call evangelical Christianity tomorrow. Evangelicals are increasingly being viewed as a group with strange beliefs.