Index: wp-admin/edit.php
===================================================================
--- wp-admin/edit.php	(revision 4540)
+++ wp-admin/edit.php	(working copy)
@@ -127,7 +127,7 @@
 <?php
 // define the columns to display, the syntax is 'internal name' => 'display name'
 $posts_columns = array(
-	'id'         => __('ID'),
+	'id'         => '<div style="text-align: center">' . __('ID') . '</div>',
 	'date'       => __('When'),
 	'title'      => __('Title'),
 	'categories' => __('Categories'),