From personal experience, I can tell you that creatine will cause an initial 7-10 lb weight gain over a period of less than a week as a result of increased water retention in your muscles (making them look bigger. stronger and fuller but less "ripped"). Creatine causes skeletal muscle to retain more water.
Creatine also acts as muscle fuel, allowing you to push your body harder in anaerobic activity (i.e weight-lifting or short, intense sprints) by delivering fuel to the muscles. It also speeds the rate of recovery within muscles and creates a (slightly) better "anabolic environment" in your muscles, maximising any gains from weight-lifting.
That being said, its role in weight loss is minimal. If you're training to bulk up, it's great (former bodybuilder trying to get back into shape here). But if you're trying to shed fat, why inflate yourself by another 7-10 lbs unnecessarily? It's also quite expensive. There's no evidence to suggest it damages the kidneys or liver, so don't let that put you off. But, is it needed to achieve your goals? What are your goals? For weight loss goals, I would say it's largely superfluous, unless you're a bodybuilder doing a short-term "cut" stage of training to lower body fat.