AJAX replace_html error

I have a query form that performs a complex SQL query based on form
params and then creates a bunch of @user_x collections for display
purposes. However, AJAX is bombing out with what seems to be a simple
error. When I submit the form, instead of replacing the desired partial
(under the form) it displays:

Forgot an important part!

FORM VIEW (below form)
<% if @users %>
  <div id="query_results">
    <%= render(:partial => "query_results")%>
<% end %>