Zoli Erdos has come up with a very elaborate post titled Zoho - the "Safer Office". From his excellent post :

Zoho pumps out new applications at an amazing rate (check the site for a few more I haven't even mentioned). While one by one most of their applications are comparable to at least another web-based application, I am not aware of any other company offering such a complete suite, with that level of support and the realistic prospect of integrating the applications soon. For me the choice is obvious: Zoho is my Office 2.0 Suite.

We can't ask for more! Thanks a lot, Zoli :-)