GamersUplink have posted up the transcript for the City of Heroes IRC Chat they had with developer, Jack Emmert. Heres a bit:

    Alex: New and fresh stories are so important to a MMORPG. Will CoH contain regular events/large content changes? Or will the bulk of the updates be focused on tweaks/fixes while content changes come in the form of expansions?

    Jack Emmert: We have a two pronged approach. First, the game contains reactive storylines. That is, the storylines will change depending upon the actions of the players. Secondly, we'll be releasing new content in the form of expansion packs. Such as: the Underwater pack, the "other dimension" pack, Vehicle pack, etc.