The main concern should be users privacy and with that comes their passwords.
Knowing this, the least thing a developer can do is to at least encrypt all the user passwords so in the event of a hacker gaining access to the database, the hacker will expose unusable information. I don’t think so, he may have some emotional issues as can be seen from reading his post but he is not a total idiot.
A person that single handedly was able to create the largest online dating empire on the Internet can’t be that stupid.
UPDATE: Thanks to the Hacker News community for voicing their criticism and making some great points on web security and password management. Last week Plenty Of Fish got hacked and a big drama ensued after Markus Frind, its Founder and CEO, wrote a long rambling article accusing a 23 yo Argentinean hacker, Chris Russo, of extortion and harassing him and his wife.
Markus blog post caused what seems to be now the worst PR nightmare any company could dream of.