My point of view about chat situation :

• old module (if I remember well we created it when we started the development of 2.0)
• three methods than even Moodle expert admin users are not aware about.
• JS versions have different UI per methods.
• globally the chat module needs some love (maybe one chat only that work for everybody. Screenreader are mostly only used with JS. Need to study if the dameon method is still necessary in 2013, AJAX/Normal methods what's the deal...)