I think the Note 4 will be Samsung first 64bit Smartphone, Qualcomm will have the 810 out by then which is suppose to be 64bit, also Android 4.5 or 5.0 is also rumoured to be 64bit aswell.
Memory will be 4GB
Internal storage will be same 32GB as standard
Micro SD support for 256GB, which is rumoured to be out by the end of 2014
Screen 5.9" QHD
Better battery
Camera slightly improved on the S5 snapper, still be 16MP and offer all the features the S5 camera offers, maybe even OIS this time around.
Improved fingerprint scanner
Design will still probs be plastic unfortunately & it might not be water resistant, due to the S Pen, unless they find a way to seal up the slot the S pen fits into without being annoying.
KNOX's security will hit a new high in pissing off those that like to root & install custom roms, by locking it down so you can't even think about rooting or putting a custom rom on it without it flagging up 0x1