MVC Bulk Edit - Linq to Sql List Save

<%
using (Html.BeginForm())
{
%>
        <div id="items">

<%
            foreach (var task in ViewData.Model)
            {
                Html.RenderPartial(
                    "TaskEditor",
                    task,
                    new ViewDataDictionary(ViewData)
                            {
                                {"prefix", "tasks"}
                            }
                );
            }
%>

        </div>

        <input type="submit" value="Save changes" />

<%
    }
%>

<div>
<%= Html.Hidden(ViewData["prefix"] + ".index", ViewData.Model.Id) %>

<% var fieldPrefix = string.Format("{0}[{1}].", ViewData["prefix"], ViewData.Model.Id); %>

<%= Html.Hidden(fieldPrefix + "Id", ViewData.Model.Id) %>
Description:
<%= Html.TextBox(fieldPrefix + "TaskDescription", ViewData.Model.TaskDescription)%>
Date:
<%= Html.TextBox(fieldPrefix + "EntryDate", ViewData.Model.EntryDate.ToString("o"))%>
Completed:
<%= Html.CheckBox(fieldPrefix + "IsCompleted", ViewData.Model.IsCompleted)%>
</div>

[AcceptVerbs(HttpVerbs.Get)]
    public ActionResult BulkEdit()
    {
        var tasks = from t in db.Tasks orderby t.EntryDate descending select t;

        return View(tasks.ToList());
    }

    [AcceptVerbs(HttpVerbs.Post)]
    public ActionResult BulkEdit(IList<Task> tasks)
    {
        foreach(Task task in tasks)
        {
            foreach(Task dbTask in db.Tasks)
            {
                if (dbTask.Id == task.Id)
                {
                    dbTask.TaskDescription = task.TaskDescription;
                    dbTask.EntryDate = task.EntryDate;
                    dbTask.IsCompleted = task.IsCompleted;
                }
            }
        }

        db.SubmitChanges();

        return RedirectToAction("Index");
    }

db.Tasks = tasks;