I have two controllers and share data between them with an app.factory function.
The first controller adds a widget in the model array (pluginsDisplayed) when a link
If you add a $scope.$apply();
right after $scope.pluginsDisplayed.splice(index,1);
then it works.
I am not sure why this is happening, but basically when AngularJS doesn't know that the $scope has changed, it requires to call $apply manually. I am also new to AngularJS so cannot explain this better. I need too look more into it.
I found this awesome article that explains it quite properly. Note: I think it might be better to use ng-click (docs) rather than binding to "mousedown". I wrote a simple app here (http://avinash.me/losh, source http://github.com/hardfire/losh) based on AngularJS. It is not very clean, but it might be of help.