This is a bug with WP 3.4 – I’ve posted a ticket (http://core.trac.wordpress.org/ticket/20953)
If you want to fix it right now, go into functions.php (in /wp-includes/) and on line 3625 you change
$trace = debug_backtrace( false ); to $trace = debug_backtrace();
It will solve your problems for the time being. Also, tell your host to update the PHP-version the server is running (it is because the old version that this error occurs).
To clarify, the posts doesn’t appear on other peoples stream. They have to click on my profile to see my post… Which isn’t very useful…
