Earlier quoted context omitted.
Statement by freenode because of the block http://blog.freenode.net/2009/06/new-freenode-webchat-and-wh... Analysis: Seems like mibbit was being abused and it was difficult for freenode to combat the abuse. Freenode eventually just got fed up with all the time required to fix the problem. It was too easy to get on mibbit to evade a ban to screw with a channel.
They also claim that the communication and collaboration with Mibbit wasn't easy. Direct link to their new web IRC client: http://webchat.freenode.net/
Damn, so many nice things written in Python .. guess it's time to learn it : /