I actually had a conversation with someone who said they didn't like this game, and though I understand her criticisms, for me, Skyward Sword was just a lot of fun.
The Legend of Zelda has always had one very important question, "How can it be possible that Zelda, Link, and Ganon exist in multiple times, Hyrules, and always seem to meet each other?" This especially becomes a poignant question when you consider that there is an actual timeline for Legend of Zelda.
Skyward Sword set out to be the true origin for the series, and answer that important question. What we got was a fun experience full of both insightful moments, and plenty of nostalgia.
If you haven't heard me say this before, I'm a story guy, so when I heard there was going to be more story to both Zelda and Link this go round, I was thrilled. Don't get me wrong, they've been fleshed out before in certain ways, but you always wanted more. In Skyward Sword, we got just that. No longer were they just "randomly encountered" and worked together to save the world. Here, in the land of Skyloft, they were friends...and hinted they could be more than that.
Then, when Zelda (inevitably) gets kidnapped, Link is now going to rescue a friend and not just person he just met. Context is important, and this one was spot on.
Also though, there was a lot of stuff to do despite having "limited" places to go. Skyloft alone was big and full of things to explore. Especially since you could fly around on your winged bird.
Then there's the gameplay, which was specifically made for the Wiimote and Nunchuk. I really liked the tight controls, and innovative use of certain weapons through them. It really added a nice flavor to things. Add to that new enemies, including a now fan-favorite Ghirahim, some pretty epic boss fights, and the beginning of an unfolding world that we know the end result of, and you have an instant classic.
Skyward Sword had a lot of presure on it going into development, our expectations were high. To me? It met every one of them.