Samsung has revealed a folding active matrix OLED display, claimed to be the first, at Japanese display show FPD International. 
Seen here:
Samsung 
claims the display is 0.5mm thick and WQVGA (480xRGBx272), with above NTSC gamut 8-bit colour.
Intensity is 200Cd/m² and claimed life is 20,000 hours, credited to "thin film encapsulation". If this display has plastic substrates, as opposed to two glass substrates folding together, this is an exceptional lifetime.
The firm also showed displays that definitely had plastic substrates at the same show:
See also: Electronics Weekly's Focus on Samsung Electronics, a roundup of content on three main areas of the technology giant's development: memory chips, LCD displays and mobile phone technology.
See also: Electronics Weekly's roundup of content related to LEDs, with a special focus on both white LEDs and coloured LEDs:
LED technology - White LEDs
LED technology - Coloured LEDs
LED technology - LEDs general
LED technology - LEDs Lighting