But Inniu may well be making money from the incoming (diverted) calls as they could have things arranged so that they receive at least part of the network termination charge - voila, they have a business model (of sorts!).

Whether their product works out for you seems to be pretty dependent upon whether your price plan lets you use your inclusive minutes for call diversion - if not, you're paying for every second someone leaves you a long and laborious voicemail message! Of course the ability to have said messages delivered by email might suit your needs. I'm happy with old fashioned voicemail, but maybe I'm just complacent!