Samsung is expected to launch the Galaxy S5 in a few months, and there are many rumors regarding this upcoming phone. The latest report from Korea says that SDC started producing 5.25" WQHD (2560x1440, 560 PPI) AMOLED panels that will be used in the GS5. The display uses the same Diamond Pixel arrangement as in the GS4.
Earlier rumors suggested that Samsung will adopt a flexible YOUM OLED for a premium version of the GS5. As a reminder, the flexible OLED in the Galaxy Round (which can be considered a Note 3 variant) is not a YOUM display as it is uses a glass cover.
A couple of weeks ago we also reported on rumors that Samsung will adopt an LCD for the GS5 (and the Note 4). This is highly unlikely though as Samsung it was made clear that they will continue to adopt OLED displays in their high-end devices.