Really looking forward to merging all my similar type folders and reduce screen clutter. At the moment I have many "Games apps" because they don't fit into a single one. I have sports games, normal games, free games, simulation games and two kids games. Be great to combine these in one folder.
I also have a football folder, a golf folder and a general sports one so I can merge these too.
Also, I'm intrigued by the Photo Roll changes and grouping. I didn't entirely follow how this worked from the presentation back in June. I know it goes by date and then groups those taken at the same time.
Control centre will be great as will Airdrop (but as I don't have a iP5 or an iPad4 I'll need to wait until I can upgrade next year).
Since this was announced in June I have been looking forward to it, and from the pictures I have seen, I really like the design of it too.