The creatures outside looked from pig to man, and from man to pig, and from pig to man again; but already it was impossible to say which was which. (read entire book here)The phenomenon of the revolutionaries repeating the behavior of those they fought against was certainly present in the LDS church as well. For example, Joseph Smith preached against adultery and other lustful acts (e.g., Jacob 2). He founded his church promising purity and chastity to those who would follow him. Of course, once he had established his power, he became the very thing he preached against; he took a large number of wives, often from their first husbands, several of them teenagers (source). He and his early elite became the adulterers they professed to condemn (those who disagree are first directed to this post, then feel free to respond).
Another common theme throughout Orwell's writings is that the leaders allow themselves special privileges that are strictly forbidden to the followers. For example, in 1984 (full text here), the high members of the Party have control over the devices monitoring their movements and speech, may have quality chocolate and other such comforts not permitted to the rest of the society. The elite members of the Party may make exceptions to their own rules as they see fit. They are somehow above their own laws: requiring the followers to practice restraint, but not themselves.
This is also true of Joseph Smith, Jr.; his own conditions for the practice of polygamy were that (a) it be only for the purpose of producing children (Jacob 2:30), (b) plural wives must be virgins (D&C 132:61), (c) the plural wives may not belong to another man (also D&C 132:61), and (d) the first wife must give her consent (also D&C 132:61).
Smith followed not one of these conditions: (a) he produced, at most, 3 children from extramonogamous marriages (Compton, 2001; Embry, 2007); (b) he married at least 15 women who were not virgins; (c) at least 11 of whom belonged to their living husbands (Compton, 2001); and (d) Emma did not give consent until 1843 - years and wives after Smith started the practice (Brodie, 1945; Embry, 2007). Thus, Smith felt that he was somehow above the conditions of polygamy he set forth. Somehow his rules did not apply to himself. So we see that the LDS church is no exception to the corruption that comes with power.
Thus, while Orwell demonstrated how pigs, when given ultimate power, become the men they despise, Smith showed us how men, when given ultimate power, become the pigs they despise.
References
Brodie, F. M. (1945). No man knows my history: The life of Joseph Smith. New York: Vintage Books.
Embry, J. L. (2007). Setting the record straight: Mormons and polygamy. Orem, UT: Millennial Press, Inc.