At CES 2012 in early January in Las Vegas, Nokia will introduce two new smart phones - Lumia 900 and 719. Both devices will be managed by the operating system Windows Phone Tango, which will be also announced in the CES.
Characteristics of smart phones are not reported, but based on the names it is clear that Lumia 900 is high end solution, and Lumia 719 - mid-level, which will take place between models 800 and 710 Lumia. As for Tango, then its key feature will be the support for wireless LTE.
In the middle of June 2012 is expected to release Windows Phone OS 8 Apollo.