Bosch is probably the best known of all the dishwasher brands, and have a reputation for producing good quality, middle of the road appliances. Like most well known brand names, you know what you're getting with a Bosch dishwasher - a good quality, dependable, sturdy machine. Whilst Bosch have a whole range of dishwashers, they are generally in the mid range price bracket - their best dishwashers will be nearer the top of the price range, but they also produce value dishwashers nearer to the bottom.
Bosch typically offer a variety of features on their dishwashers - some may just be mere gimmicks aimed to get stock off the shelves, but a lot of the features Bosch offer are genuinely useful. Try to bear in mind the practical use of each feature when browsing dishwashers, and whether it is really necessary for your needs.
One feature specific to Bosch is AquaStop, which can detect when there is a leak, and automatically stop the dishwasher, thus preventing any flooding and consequent damages to your kitchen. Some machines can detect the level of soilage of the dishes, and adjust the wash cycles accordingly (by changing both the length of the cycle, and the temperature) - this may be important to you if you are environmentally minded, or simply want to keep the bills down.
With all these features, it's easy to be tempted by the more expensive Bosch dishwashers - however, this is probably not the best idea. For the same amount of money as a top of the range Bosch dishwasher, you can get a higher end brand, like Miele. Whilst a Miele might not have all the bells and whistles of a top end Bosch, it will offer a higher all round quality. Having said that, Bosch are hard to beat for mid range, good value dishwashers, and have a reputation for producing quiet machines. Bosch dishwashers are well recommended, and if you are on any kind of budget, you might not need to look any further than a Bosch.