changed some-site.com to example.com in example code per http://www.rfc-editor.org/rfc/rfc2606.txt
diff --git a/user_guide/libraries/trackback.html b/user_guide/libraries/trackback.html
index c5a50f0..02eeaa9 100644
--- a/user_guide/libraries/trackback.html
+++ b/user_guide/libraries/trackback.html
@@ -83,8 +83,8 @@
<code>$this->load->library('trackback');<br />
<br />
$tb_data = array(<br />
- 'ping_url' => 'http://some-site.com/trackback/456',<br />
- 'url' => 'http://www.my-site.com/blog/entry/123',<br />
+ 'ping_url' => 'http://example.com/trackback/456',<br />
+ 'url' => 'http://www.my-example.com/blog/entry/123',<br />
'title' => 'The Title of My Entry',<br />
'excerpt' => 'The entry content.',<br />
'blog_name' => 'My Blog Name',<br />