When Samsung announced the Galaxy Note 2, with its 5.5" 1280x720 HD Super AMOLED display, I assumed it was a Pentile display. But it seems that the Note 2 actually uses an RGB matrix in a unique arrangement (see the photo below). Samsung calls this new matrix S-Stripe. This is rather confusing on several accounts - mostly because up till now Samsung used the brand Super AMOLED Plus for non-pentile OLEDs.
Just a few weeks ago we explained that Pentile OLED displays enable higher lifetime, and we were told that for an RGB OLED with over 230 PPI, lifetime becomes too low for Samsung and they choose Pentile in those displays. But the Note II has a PPI of 267 - the highest PPI non-Pentile OLED. This means it has a lower lifetime compared to a Pentile display (but the advantage is that there's no visible Pentile pattern of course).
It seems likely that Samsung managed to increase the lifetime of their OLED displays, and so were able to ditch the Pentile here. It's possible that Samsung have finally started to use green PHOLED emitter (which improves the lifetime over the green fluorescent emitter used in current displays), and perhaps they have also moved to a better fluorescent blue emitter.