The fashion industry is the most obvious choice for color trends, with Pantone choosing the "color of the year" - emerald green this year, btw. I'd like to sit in on that meeting, as someone decides, "Let's tell them they love mauve!"
Animal trends are many and tend to return again and again. Elephants, owls, and frogs were as popular in the '60's as they are today. Last year it was the octopus. The fox seems to be latest animal trend. Nautical themes return too. They are well suited to my kumihimo bracelets, as are the animal, so you'll see a lot of these in my shop.
What's your favorite new craze?