Watching streams is the equivalent of watching a game of baseball, or any sport. Not only is it often fun, it will teach you a lot about how the best play the game. No one is telling you that's how to play the game, but when you have troubles doing something, streams show you a technique that is successful enough to be used professionally.
In terms of jungling though, the new jungle gives less experience, but since the camps respawn faster, you still should be able to make the same times as the previous jungles. If you're playing a champion who isn't the fastest (ww, alistar, fiddle), try to gank more often to make up for poor jungling speeds. Understand if your champion is better for ganking, or clearing, and prioritize from there.