It's difficult to know exactly how to handle a new installment in a franchise that's been around as long as The Legend of Zelda. Stick to what made the series great, and you risk feeling stale, but break too far away from expectations and long-time fans may feel betrayed. The Legend of Zelda: Skyward Sword is the perfect tribute to its impressive lineage, honoring its predecessors while maintaining its own identity. If you're a long-time fan of the franchise, you'll love it. If you're brand new to Link and Zelda, you'll love it. Even if you've felt like the series had become tired and stale, you'll love it. It will make you believe the Legend will continue for another 25 years.
The sky island of Skyloft serves as the hub for Skyward Sword as well as Link and Zelda's home town. The Goddess brought humans to Skyloft long ago, to protect them from the monsters that were invading the surface, but the time has come for Link and Zelda to embrace their destinies and take up their roles as Hero and Spirit Maiden. Not that Link really cares all that much about such high-minded concepts like being chosen by the Goddess - he just wants to get his life-long friend out of danger and back to Skyloft where she belongs. Making Link and Zelda school pals puts a different spin on their dynamic and makes his quest to find her less about prophecies and more about personal concern. He's not cutting his way through enemies and navigating dungeon traps to satisfy a set of mystical requirements, he's doing it because he's worried about his friend.
Once you're on the surface, you'll meet new creatures, kill some of them, and puzzle your way through a series of increasingly complex dungeons. The dungeons of Skyward Sword are incredibly clever, really forcing you to be observant and think your way through obstacles. As you play, it'll become very obvious just how other games hit you over the head with answers or clues. You may feel like you already know all of Skyward Sword's tricks because you're a longtime Zelda fan, but don't be too sure. There are certainly familiar mechanics, like finding small keys to unlock doors, or bombing your way through cracks in walls, but these dungeons have plenty of new ideas.
You'll probably be baffled more than once, but Skyward Sword has a few tools to get you back on track. Using your sword like a divining rod, your new dowsing ability helps point you toward important items like key pieces, hearts, or your little blonde friend. Your spirit companion, Fi, can give you intel on your enemies or hints about puzzles, though her advice usually boils down to "look around, dummy." A stone back in Skyloft even provides video clips spelling out how to make it past particularly tricky sections. The hints are a nice fallback for newer players or for when you become truly stuck, but getting out of a dungeon and back to the stone is enough of a pain that you'll really have to want that clue.