I think part of the confusion is that the word "cult" is used in two ways. One is doctrinal/theological; the other is the coercive/mind-control aspect. Steven Hassan does classify Mormonism as a cult according to the second definition. I don't have time to figure out how to insert a link, but if you go to Freedomofmind.com, there is a great piece on the BITE model applied to Mormonism, especially the young Mormon missionaries. (or google BITE model mormon missionaries.)
I have seen the controlling aspect close up. Long story, but a young man our whole family spent a lot of time with ever since he was in diapers - has basically cut off our whole family since he became an "elder." (He posted that on his FB, made me cringe!) I never once spoke with him about anything concerning his family's religion.
One way i gauge whether a group is a cult, or at least cult-like, is asking - if you were born into it, can you leave it when you come of age, and still maintain warm and loving relationships with your family members? At least in the area where i live and the Mormons we know, no, they can't get out of it. Some have literally been kicked out of the house. A guy at my daughter's school lived with various friends who would take him during his last 2 years of high school, as he didn't want to be LDS.