Last week we reported that Samsung decided to use OLED technology in its upcoming Full-HD mobile phone display, and today we hear that Samsung plans to unveil this panel at CES 2013 (January 8-11). The panel's size is 4.99" which means 441 PPI (at 1920x1080). Back in October it was reported that Samsung managed to reach 400 PPI using a modified FMM technology.
A 4.99" display is quite larger than the S3 (4.8") and it's not clear whether this will be used in the upcoming S4 phone (I think there's a limit to the size of Samsung's main flagship smartphone). The Note II has a 5.5" display, so the new panel is somewhat between those two phones. Samsung may be able to put this larger display into a case with the same as as the S3 one, by narrowing the bezel and perhaps removing the home button.
Some people question whether such a high PPI is actually required. The highest PPI AMOLED ever made is the one used in Samsung's Galaxy Nexus (316 ppi: 4.65", 1280x720, with PenTile technology). The S3 has 306 ppi (4.8" 1280x720, PenTile) and the Note II has only 267 ppi, 5.5" 1280x720 - but without PenTile. The iPhone features 326 PPI. But other display companies (including Sharp, LGD and Japan Display) have already unveiled Full-HD mobile displays, so Samsung probably just plays marketing catch-up.