When photographers talk about a "faster" camera or lens, they are often talking about the light-gathering capability. A "fast" camera is one that can use a faster shutter speed, given the same environment, than a "slower" camera. This has to do with the maximum aperture size of the lens and the speed of the film (or sensor). In digital cameras, which I don't know much about, I understand that "noise" is an issue in low light conditions, which would be another form of "slowness", since you'd need a longer exposure to deal with this. The sensor may function like relatively slow-speed film in digital cameras. I know most digital cameras have ISO settings up to 1600, but I also understand this comes with quite a lot of noise in the image. For usable quality, I can imagine that a digital camera is "slower". Then again, film cameras also give extraordinarily higher quality, especially with slow film or negatives larger than 35mm, so comparing like-to-like image quality is a fool's endeavor anyhow.

Are you sure he wasn't talking about exposure time and not time between successive shots?