Okay so I don't really have a "favorite" Zelda game, mostly because each game in the series is so paradoxically different yet the same as each other it makes it hard to choose. I used to like Wind Waker the best, then I liked Twilight Princess the best, then Ocarine of Time, then Link's Crossbow training. Okay maybe not that last one, but you get my point. There are a bunch of things I liked about Skyward Sword that haven't been in the series before (like the motion plus combat) and upgrading items with collectibles, and I really liked how they made each item you get more relevant throughout the whole game rather than just the dungeon you found it in. I liked the boss fights and how the game was a bit more challenging than a few of it's predessesors. I liked the more Majora's Mask-esque NPC sidequests and how they characterised the NPCs, and I also liked the story overall. I don't know I just like it and can't think of anything to complain about except nitpicks, but that's how most Zelda games go for me at least.