Well, Toktumi is designed for setting up a workgroup of phones along with a professional auto-attendant, a touchtone directory for callers, and other business-class features. Magicjack is designed for a single user (single line), while Toktumi is designed for a small office with multiple lines. Toktumi requires software on PCs to run, but the business-class features (auto-attendant, voicemail, conferencing, etc.) is done on Toktumi's servers. A more comparable comparison might be with Packet8's Virtual Office offering.
One unique feature is you can dial into the service via your cellphone and receive a second dial tone that enables you to dial out over the Toktumi network. The callee would see the user's Toktumi number on their Caller ID instead of your personal mobile phone number. This is useful for mobile business professionals that wish to use their personal mobile without giving out their personal number.
Pricing is per phone number per month and both unlimited and per minute usage options are available. A 30 day trial is also available. It'll be interesting to see if Toktumi can duplicate the success of the Magicjack. Magicjack has one huge advantage going for it - namely it's super low-price. Will small businesses or home businesses be willing to pay an extra $159.41 per phone line per year for the added benefit of an auto-attendant, 20-person conferencing, call transfer, voicemail, and a few other features?