N-Sider Robert W. was both patient and quick enough to catch the 1 millionth Nintendo Wi-Fi Connection user. He was on a Linux machine and noted the time at 12:40 GMT. After capturing the screen he observed, "...one minute later, another 16 users had logged on. I guess everyone wanted to be 1,000,000th."

Nintendo Wi-Fi Connection one millionth user screen

Thanks Robert. Also thanks to Jiran and Dylan for their effort.