It could learn a lot. Maybe not story wise, although we don't know yet how the story will turn out in Skyrim, but Nintendo could inject some of Beth's world building into Zelda.
Bethesda's world designs don't really suit Zelda's style of play. There's virtually no platforming or opportunity to make use of the tools one acquires over the course of the game and it doesn't strike me as a very good design for collectables either (heart containers, bomb/arrow upgrades, etc.).
I wouldn't even like to see the size of Bethesda's maps applied to a Zelda game as it is (/flameshield) mostly wasted space. Aside from roleplaying (which has never been the draw of Zelda), why on Earth do we need such large maps? Zelda's worlds have always made sense according to the amount of content found in the game. They don't just up the map size for the sake of being bigger, which is something that's always turned me away from open world games.
Nintendo could easily get away with making larger, more intricate maps, but they can do so in a manner that best suits their game rather than borrowing from one whose design is wildly different.