i hadn't touched the wordpress core (as i mentioned above) but here is the relevant code anyway
single.php (i commented out the original code to debug; no avail - there is simply no output from the_content)
<!-- <?php the_content( __('<p>Read the rest of this entry »</p>', 'arras') ); ?> -->
<?php the_content(); ?>
<?php wp_link_pages(array('before' => __('<p><strong>Pages:</strong> ', 'arras'),
'after' => '</p>', 'next_or_number' => 'number')); ?>
i use the Arras theme and so this was my home.php which also stopped working.
<span class="entry-title"><?php the_title(); ?></span>
<span class="entry-summary"><?php echo arras_strip_content(get_the_excerpt(), 20); ?></span>
sorry folks i think its pretty clear that the_content is supposed to run from my server, but i didnt touch any of it so i really cant figure out why its not outputting a single thing.