Update, going off what Frank wrote below:
In my post's show view I have:
<span id="commentsPartial">
<%= render 'comments' %>
</span>
In the comments partial I have:
<% @comments.each do |comment| %>
<%= comment.description %>
<% end %>
<br/>
<%= render '/comments/form' %>
In my form partial I have:
<%= form_for [@comment], :remote => true do |f| %>
<% if @comment.errors.any? %>
<div id="error_explanation">
<h2><%= pluralize(@comment.errors.count, "error") %> prohibited this comment from being saved:</h2>
<ul>
<% @comment.errors.full_messages.each do |msg| %>
<li><%= msg %></li>
<% end %>
</ul>
</div>
<% end %>
<div class="field">
<%= f.text_area :description, :class => "forms", :style => "width:80%;height:120px;"%>
</div>
<div class="actions" style="margin-top:10px;">
<%= f.hidden_field :user_id, :value => current_user.id %>
<%= f.hidden_field :post_id, :value => @post.id %>
<%= f.submit :class => "button-style" %>
</div>
<% end %>
My views/comments/create.js.erb page has:
$("#commentsPartial").html("<%= escape_javascript(render('comments')) %>");
When I submit a new comment - it is successfully created. The page however remains static. When I watch in firebug, I see the comment is created, and there is a get called on the post which returns a success - even though the page doesn't update... very confused