We've got new details about the resolution of Samsung's Super AMOLED Plus. Super AMOLED Plus drops the PenTile matrix used in Samsung's previous generation AMOLEDs, and so have 50% sub pixels (see explanation here). This causes it to be clearer, but actually each pixel is a bit larger and so a 4.3" Super AMOLED Plus display features the same resolution as a 4" Super AMOLED.
But we were also told that Samsung will produce Super AMOLED Plus at higher resolutions - and achieve over 300ppi. Today we learned that Samsung plans to move from Fine-Metal-Mask (FMM) technology to laser-induced thermal imaging (LITI). This will enable them to achieve much higher resolutions. We do not know when they plan to actually start using LITI, but when they do they'll be able to produce displays with much higher resolutions (on par with Apple's Retina-Display).
FMM uses a Shadow Mask and is actually a very expensive method but up till now it's been the only available method for AMOLEDs. It limits the resolution to 200ppi as it has a printing accuracy of about 15 micro meters. LITI uses laser and has a printing accuracy of about 2.5 micro meters - so it can achieve over 300ppi, while being cheaper than FMM, too.
It is likely that Samsung will re-brand these next displays - to differentiate them yet again. So we can expect the to announce a 'Super AMOLED HD' display sometimes in the future - which will have higher resolution that Super AMOLED Plus and hopefully will be even cheaper. LITI is also an important step towards the commercialization of OLED TVs...