The number of nodes shown on the content admin page (admin/content) is still hardcoded to the value "50" in node.admin.inc:
<?php
$nids = $query
->fields('n',array('nid'))
->limit(50)
->orderByHeader($header)
->addTag('node_access')
->execute()
->fetchCol();
?>This is especially bothersome when trying to delete lots of content (e.g. after importing test data).
See #7743: let admins mass delete nodes for this feature request since ancient times.
I once wrote a small core hack to make this setting configurable: "Increase the number of nodes per page when administering content".
It would be great if this would become a core feature some day.