The serial number and MAC address will follow the Pi, not the SD Card. Plugging a cloned SD card into a different Pi will change the serial number and the MAC address. If you think about it, any new Pi with a new image from the download link above will be a clone anyway.
I have one SD card image that I have updated/upgraded and added packages to my liking. I am using this image as a base for any additional SD cards I will be using in other Pis. This works just fine. I create a disk image with dd.
Questions: 1) In creating an exact copy of the SD card, I am also picking up the MAC and serial number of the original Pi, how do I maintain the MAC and serial for each additional Pi I plug the cloned SD card into? 2) Is there a way to determine the burnt in MAC of each NIC?