Many of us wanted a new villian. I think the Interlopers were high on the community's list of most wanted villians, and it's looking like they may have delivered with Ghirahim. Even if he isn't one of the Interlopers who created the Fused Shadow, he still seems like a very interesting character, and quite a refreshing change-up. His mannerisms and reckless demeanor frighten me in a way Ganondorf's power never could.
This is hundreds of years before OoT and Ganondorf is not even born. I don't expect to see him, but I do expect some backstory to give us a lead as to his relevance in the future of the series. One possible take on this subject could be the origins of Koume and Kotake, who existed hundreds of years before OoT, and could very well exist during the events of SS.
Time will tell, but I'm certainly excited to experience this prequel. The story telling is already looking fantastic, so my hopes are high for a bit of Zelda lore to wet my taste buds.