What is the future of asynchronous classrooms?

Having worked with, experimented and tested several asynchronous, collaborative 'classrooms' I have come to the conclusion that while some effort has been made by software developers to accommodate purely educational institutions with the inclusion of certain features and functions, most platforms have grown from the needs of medium - big business to train their workforce.

My interest here is to encourage other educators to evaluate their needs and requirements of virtual online classrooms.

Which classrooms have you tried? What were there strengths and weaknesses?
What features would you include to make the online learning experience more valuable and productive for students and teachers?

I look forward to the responses that follow.

Regards,

Andrew Fleet