I think Google, ever since it first came out I have used it... I never liked yahoo, google has always been more reliable. now microsoft on the other hand is completely diffent and I dont really know how to compare the two but I would always say google, google has been expanding in any way possible from its youtube deal to the new G-phone that has recently come out. google maps, scetch 3d and tons of other products, goodle is working hard and doing many things it is just destined to stay big, microsoft and yahoo on the other hand are still at work but nothing of the same size. no matter wich one you want to like you cant help but think google will do better, luckily I love google so I m happy with it.