GetUserProfileProperty.js

rjeshns.getUserProperty = function (profileProperty) {
    var deferred = $.Deferred();
    var clientContext = new SP.ClientContext.get_current();
    var peopleManager = new SP.UserProfiles.PeopleManager(clientContext);
    var personProperties = peopleManager.getMyProperties();

    clientContext.load(personProperties);
    clientContext.executeQueryAsync(

    Function.createDelegate(this,
                function () {
                    var userProperty = personProperties.get_userProfileProperties()[profileProperty];
                    deferred.resolve(userProperty);
                }),

            Function.createDelegate(this,
                    function (sender, args) {
                        deferred.reject(sender, args);
                        rjeshns.LogError(args.get_message());
                    })
    );
    return deferred.promise();
}