What does a flash bracket get you? If you put your flash on the camera and use it in portrait orientation, you will get a shadow on the left side of your subject (camera right), eliminating this shadow is the primary reason for a flash bracket. By raising the flash up a little, you also decrease the chance of red-eye. The other thing a bracket gets you is ease of use. If you are bouncing the flash then you never have to change the head. If you use the flash on camera then you must change the head everytime you change orientation.
There is an argument out there as to how high to raise the flash above the camera. Some brackets jack the flash 6 or more inches above the camera, while some only go little if any above the normal height. Going higher means less of a chance of red-eye, but then you have to worry you will get shadows under the nose, chin and eye sockets.
In the pictures above, provided by CDIfoto, that is a Newton Flash Rotator bracket. He uses the philosphy of just raise the flash a little. This is also the backet I use. I love mine and wouldn't use anything else. Part of what sold me was how light and compact it is. It is one of the lightest out there. Its not the cheapest. They run about $200 but you will never have to buy another.
I don't get red-eye while using mine and all you do is flip it up and wah-lah, your good to go. I wouldn't do a wedding without one. There are lots of opinions on this matter and you will have to decide for yourself. I can only tell you my experiences. I know Mr. Newton will gladly talk to you if you have any questions about his products. He also has a camera rotator model. Which one to use? If you mainly use the camera hand held then I believe he reccommends the flash rotator and if you use a tripod alot then the camera rotator model is best for you.
One other reason I chose the flash rotator is that I use a 24-105. The zoom ring is very close to the camera body and is very narrow. The camera rotator has part of the backet going up the left side of the camera and I was worried it might get in the way a little of my lens zoom ring. This and my main use is weddings so its mostly hand held. Hope some of this helps. Mark