Samsung's Game Pad accessory for the S4 hints a 6.3" Galaxy Note III is indeed in the works
Samsung has done the usual microsite for everything Galaxy S 4-related, including the world of accessories its latest will come with. tucked among them is the Game Pad contraption, that combines a gaming pad with a phone holder for the avid timewaster in you.
In the Game Pad's description, however, this nugget of information is disclosed: "4"~6.3" size available". Given that the Samsung Galaxy Note III has been rumored to come with a 6.3" Full HD display, this should serve as another confirmation that the company's fabled phablet would indeed arrive with a 6"+ display come the holiday season.
Seeing what Samsung did with the S 4, it is also probable that while the screen size will grow, the dimensions will stay the same or even more compact than the Note II.