This is the Angular.js directive that converts html select boxes with Angularjs bindings into the Twitter Bootstrap dropboxes. See examples on jsfiddle: http://jsfiddle.net/M32pj/28/

gistfile1.js

angular.module('bsselect', [])
.directive('bsSelectbox', function ($parse) {
    return {
        restrict: 'A',
        priority: 100,
        transclude: true,
        scope: {
            themodel: '=ngModel',
            thearray: '@ngOptions',
    		thechange: '&ngChange',
            defaultval: '@bsSelectbox'
        },
        template:
            '<div class="bs-selectbox btn-group">' +
            '<button class="btn dropdown-toggle" data-toggle="dropdown" type="button">' +
            '{{display}} ' +
            '<span class="caret"></span>' +
            '</button>' +
            '<ul class="dropdown-menu">' +
            '<li ng-show="defaultval">' +
            '<a href="javascript:" ng-click="change(false)"> <span>{{defaultval}}</span> </a>' +
            '</li>' +
            '<li ng-show="defaultval" class="divider"></li>' +
            '<li ng-repeat="itm in elements" ng-class="{active:itm.value==themodel}">' +
            '<a href="javascript:" ng-click="change(itm)">' +
            '<span>{{itm.label}}</span>' +
            '</a>' +
            '</li>' +
            '</ul>' +
            '<div style="display:none;" class="bs-selectbox-transclude" ng-transclude></div>' +
            '</div>',
        link: function (scope, element, attrs) {
            scope.display = '--';
            scope.elements = [];
            attrs.$observe('bsSelectbox', function (value) {
                if (value) scope.display = value;
            });
            attrs.$observe('ngOptions', function (value, element) {
                if (angular.isDefined(value)) {
                    var match, loc = {};
                    var NG_OPTIONS_REGEXP = /^\s*(.*?)(?:\s+as\s+(.*?))?(?:\s+group\s+by\s+(.*))?\s+for\s+(?:([\$\w][\$\w\d]*)|(?:\(\s*([\$\w][\$\w\d]*)\s*,\s*([\$\w][\$\w\d]*)\s*\)))\s+in\s+(.*)$/;
                    if (match = value.match(NG_OPTIONS_REGEXP)) {
                        var displayFn = $parse(match[2] || match[1]),
                            valueName = match[4] || match[6],
                            valueFn = $parse(match[2] ? match[1] : valueName),
                            valuesFn = $parse(match[7]);
						scope.$watch(function(){ return valuesFn(scope.$parent); }, function(newVal) {
							var collection = newVal || [];
							scope.elements = [];
							angular.forEach(collection, function (value, key) {
								loc[valueName] = collection[key];
								scope.elements.push({
									'label': displayFn(scope.$parent, loc),
									'value': valueFn(scope.$parent, loc)
								});
							});
							scope.setdefault();
						});
                    }
                }
            });
            scope.$watch('themodel', function (newval, oldval) {
                scope.setdefault();
				if(angular.isFunction(scope.thechange) && (newval != oldval)) {
					scope.thechange();
				}
            });
            scope.setdefault = function () {
                angular.forEach(scope.elements, function (value, key) {
                    if (value.value == scope.themodel) scope.display = value.label;
                });
            }
            scope.change = function (itm) {
                if (!itm) {
                    scope.display = scope.defaultval;
                    scope.themodel = "";
                } else {
                    scope.display = itm.label;
                    scope.themodel = itm.value;
                }
            }
            var elements = element.find(".bs-selectbox-transclude").children();
            if (angular.isObject(elements) && elements.length) {
                    angular.forEach(elements, function (value, key) {
                        scope.elements.push({
                            'label': value.innerText,
                            'value': value.value
                        });
                    });
                    scope.setdefault();
            }
        },
        replace: true
    };
});

Excellent Gist. Any change you can update it to work with angular 1.2.16? I found it referenced here - http://stackoverflow.com/questions/15090185/angularjs-bootstrap-dropdown-cant-do-ng-click-in-ng-repeat but when I change the fiddle to an updated version of angular, it breaks. It can't seem to populate the ul on line 19 with the updated values.

Please upgrade your source code in ordre to $compile your template. It doesn't work with AngularJS 1.2+.
Thanks.