You can use the basic service today, which uses a web interface to chat two way with U.S. mobile phones via SMS. No registration is required. It works much like Google’s new Gmail SMS service which launched last month.
At CES, though, the company says they’ll launch a downloadable version of the service as well, for both Windows and Mac users. Having a persistent presence on the desktop will make the application much more useful (I hope it also auto-imports and syncs mobile numbers and names from my address book). A Linux version will follow, as well as MySpace and Facebook apps. The company is also white labeling the service.