Crocheting is faster and you can get different types of stitches. More artistic. Knitting is harder but I think more clean. Takes forever though. I knitted some cable knit beanies for last years snowboarding season and they turned out cute but just took forever.
This year, crochet flowers and hats are in for girls so I am taking advantage of it for my nieces. Want to try and make one of those infinity scarves too.