A Novatel Wireless MiFi filed as "4082" hit the FCC yesterday and it seems destined for Sprint, since this mobile hotspot supports CDMA/EVDO and WiMAX bands. Yet, it's too early to speculate when it will be released, but the fact is that all FCC tests have been conducted and it's only a matter of time (except if Novatel decides to apply some last minute changes and re-enter it for additional tests).
When this "MiFi 4082" is launched, it is presumed that it will join Sprint's Overdrive as another WiMAX-supporting mobile hotspot. Obviously, no price or additional details are available at the moment, but if its recently released MiFi 2372 sibling is of any indication, it may very well have its own OS.
source: FCC via Engadget