Just sent this email to webmaster@wordpress.org:

I’ve found a lot of broken links in search engines such as Google:

E.g.:
http://wordpress.org/support/11504 should be http://wordpress.org/support/topic.php?id=11504.

They seem to be broken just because the URL structure changed. Would it be possible to write some mod_rewrite rules to make these work? There’s great info on the WordPress site, but this makes it a little bit trickier to find.