SamMobile says they got some exclusive info on the upcoming Galaxy Note 4. The display will be an AMOLED panel - with a QHD (2560x1440) resolution. They do not know the display size. The rest of the spec, according to SamMobile, is a Sony 16MP camera module, and the same 2 mp front camera like in the GS5.
The Note 3, released in September 2013, has a 5.7" Full-HD Super AMOLED display (386 PPI, PenTile), a 2.3 Quad-Core CPU (or a 1.9Ghz octa-core in some markets), 3 GB of RAM, 32/64GB of storage and a a 13 MP camera. It's likely that Note 4 will have a similarly sized (or a bit larger) display.
So there we have it. This is the season we all love - a new phone from Samsung is upcoming (in a few months), and the rumor mill is starting. This is actually not the first Note 4 display rumor: Back in December 2013 it was claimed that the Note 4 will use an LCD - but then the same report also said that the GS5 will use an LCD too. In fact, when I think about it, we had so many rumors regarding Samsung's previous phones - and most of them were not true. So maybe we should attach too much into this one as well.
Following the GS5 launch, Yoon Han-kil, senior vice president of Samsung's product strategy team said that the Note 4 will have a "new form factor". We all hope that this means a flexible OLED display - maybe curved around the device edges. It is probably too soon for really foldable device (Samsung only expects these in 2015).