As a potential new customer, I would have to agree with AdrianPurnama concerns. I just don't see why anyone would want to check and verify emails with an attachment that has a known virus signature on it.
Also, I can nag my users about updated client side virus signatures, but really can't enforce it.
For what it's worth, I would be willing to pay an extra $1/month for server side virus checking ($12/year). Perhaps your marketing guru's could conduct a study/poll to see if it makes business sense? Or you could offer it as a value added service?
Besides the AV issue, so far I like your plans.
Best Regards,
Vic
