Jquery .ajax Async Postback On C# UserControl

I'm working on adding a todo list to a project system and would like to have the todo creation trigger a async postback to update the database. I'd really like to host this in a usercontrol so I can drop the todo list onto a project page, task page or stand alone todo list page.

Here's what I have.User Control "TodoList.ascx" which lives in the Controls directory.

The script that sits at the top of the UserControl. You can see where I started building jsonText to postback but when that didn't work I just tried posting back an empty data variable and removed the 'string[] items' variable from the AddTodo2 method.

<script type="text/javascript">
$(document).ready(function() {
// Add the page method call as an onclick handler for the div.
[code]...

I can have a control that can be used to display multiple todo lists and create a brand new todo list as well.When I click on the #divAddButton I can watch it build the postback in firebug but once it completes it runs the error portion by alerting 'error'. I can't see why.

I'd really rather have the response method live inside the user control as well. Since I'll be dropping it on several pages to keep from having to go put a method on each individual page.