I think the trend setter who deserves the credit is definitely Sienna Miller & her hair stylist. Remember when she wore this and everyone was on the fence about liking it. Nowadays it's definitely a loved hairstyle!
I've tried some hairstyles out with braids myself. I keep braid my hair in different ways... (I've done cooler stuff lately, but I don't have any pics of them!)
Here's some tutorials from pursebuzz for easy, super cute braid styles. Let me know how they go!