There are also returning questions about site configuration, e.g. how to configure user registration (let them verify their e-mail etc.), questions about common fatal errors (most of the time we first have to tell how they can turn on various debugging options and where they can read the debug logs) like the "Maximum execution time of x seconds..." one. Also several charset issues have been discussed a lot (converting to utf8, ...), and problems with file permissions.
Also a modification in 3.8 caused more them one forum topic ( http://ez.no/community/bugs/new_default_contentstructuremenu_ini_settings_break_existing_configurations_unnecessarily ), but I'm not sure that stuff should be in the FAQ, it should have been mentioned in the 3.8 upgrade doc, but unfortunately it wasn't.
I wasn't saying there should only be links to threads about it, but the faq should have links to threads that discuss the issue as well as explaining the answer to the faq AND have links to the parts of the doc that is involved.
One faq to fill out right away would be: "How do I hide index.php?" / "How do I enable virtual host mode?"
And a link on top of the forum that say: Always take a look thru the frequently asked questions and search for your problem in the forum before posting!