I just purchased a Nikon D5000 and it came with a 4GB card. But I wanted to get a bigger SD card, or more of them. What speeds should I be considering? I will be shooting in high quality JPEG most of the time, but I will also be using the 720p video capability. Also, I want to be able to shoot multiple pictures in a row, without any pause (or minimal pause). Give those facts, what speed card should I be looking at? And are the generic cards just as good as the name brands? Thanks!