The phone has been designed by Chris from Symbian Freak, is a public concept which Nokia could pick up if they wanted to.
From the picture above we can see immediately the main characteristic of the N-XT. It will have a display which will both slide and swivel. And here are the rest of the imagined features: 4.1 inch full-touch display with a Wide-VGA resolution of 480 x 800 pixels and 16 million colors
Symbian S60 5th Edition Touch interface
8-way D-pad
quad-band WCDMA connectivity
8 MP camera with Carl Zeiss lens, optical zoom, auto focus, face detection, xenon flash & dual-LED flash and video recording (WVGA at 30fps)
Dedicated graphics processor unit (GPU)
Accelerometer
A-GPS and compass
Built-in DLP 720p projector
Wi-Fi and Bluetooth
Audio & Video players
FM radio and FM transmitter
3.5mm audio jack
24GB of internal memory plus microSDHC support
1,800 mAh battery.
OK then, it looks good on paper. Would you like one? Would anyone care to imagine a price for it? Please keep it under $2,000 please! 
Nokia has been awfully silent lately, at least for me. Luckily I just came across a concept phone which might represent the future of the N-Series. I don’t think there are any numbers left so this N smartphone is referred to as the N-XT.
How Would You Fancy a Nokia N-XT Concept Phone?
Original source here