One of the issues against cloud computing is that of backup, in addition to security and uptime.  Microsoft is releasing new products (Office 2011) and will be fighting against cloud computing. 

Many Zoho users have been with you since the beginning. They have offered technical assistance for the improvement of your product development with forums, questions, and blogs. 

Please reconsider a backup and restore for the members of the free edition.   They have invested a lot of time into Zoho and would probably hate to lose their work.