Da, tako nesto sam i ja skuckao po preporuci ljudi da koristim JOIN umesto IN...
Ispalo je ovako, ako nekom zatreba:
Kôd:
SELECT u.`id`, u.`username`, u.`email`, u.`first_name`, u.`last_name`, sub.`moneybookers_email`, sub.cnt
FROM users u JOIN `payment` mb ON u.id=mb.`user_id`
JOIN
(SELECT count(*) AS cnt, `moneybookers_email` FROM `payment`
GROUP BY `moneybookers_email` HAVING cnt>1 ) sub
ON mb.`moneybookers_email`=sub.`moneybookers_email`
ORDER BY sub.cnt DESC, mb.`moneybookers_email`