It's the best version of the best game of all time. 'Nuff said...
Oh alright then
The 3D really adds to the game, and that includes stuff coming OUT of the screen at you, as well as adding depth! The depth makes the graphics (which look great) look even great...er, and the new lick of paint given to character models and shops (go into shops, and the shelves are packed with items etc. and there's posters of other areas of the game around as well) make it feel much better.
As for the gyroscope, it works well! It was an amazing moment moving the 3DS in 1st person mode, looking outside through the window and seeing the beauty of Hyrule field. It's a shame you can't use both the 3D effect and the gyroscope though, but it isn't hard to move a switch up and down now is it?
Oh, the new item system and maps system works well too. I'm just entering Zora's Domain, and I'm hooked all over again, and I've played every single version going (bar, sadly, the original). You'd be an idiot to miss out on this game...
(If you have any questions or anything fire away! I'll answer best I can.)