Does the speed of memory make your camera shoot faster?
It depends on your camera. Faster memory allows your camera to write an image to the memory card faster. If your camera can take advantage of the faster memory, it will take less time to be ready for the next shot.
Higher-end cameras also have internal memory buffers that allow you to take additional photos while the camera is still writing images to the memory card, in which case memory speed only becomes the limiting factor when you are quickly shooting more images than the camera can buffer.
There are several memory speeds available, and many cameras can NOT take advantage of the highest memory speeds, so buying faster memory may or may not improve the performance of your camera. Unless you’re shooting a lot of images fast, you may not notice the difference either. I personally buy fast memory for my digital SLR, but middle-of-the-road memory for my point and shoot camera.