How do I hook up twitter type ahead and knockoutJS?

HookTwitterTypeAheadWithKnockout.js

//************* HTML *****************************       
<input class="typeahead form-control"
                    type="text"
                    placeholder="Fnet User Lookup">

//************* JS *****************************                        

$('.typeahead').typeahead({
                            remote: {
                            url: myApp.rootPath + 'user/AutocompleteUser?query=%query',
                            wildcard: '%query'
                            },
                            limit: 10,
});

// where viewModel our ViewModel
$(".typeahead").on("typeahead:selected", function (e, datum) {
    viewModel.userToAdd(datum.value);
});

serverController.cs

 /* an MVC Controller */
  public JsonResult AutocompleteUser(string query)
        {
            if (!string.IsNullOrEmpty(query))
            {
                MembershipUserCollection userCollection = Membership.FindUsersByName(query);

                var results = userCollection.Cast<MembershipUser>().Select(x => new TypeaheadResult
                                {
                                    tokens = new[] { x.Email, x.UserName },
                                    value = x.Email,
                                    //userId = ToBeSetOnINSERT
                                });

                return this.Json(results, JsonRequestBehavior.AllowGet);
            }

            return this.Json(new { }, JsonRequestBehavior.AllowGet);
        }

TypeaheadResult.cs

 public class TypeaheadResult
    {
        #region Public Properties

        /// <summary>
        ///     Gets or sets the users name.
        /// </summary>
        public string[] tokens { get; set; }

        /// <summary>
        ///     Gets or sets the login email.
        /// </summary>
        public string value { get; set; }

        public int userId { get; set; }

        #endregion
    }