Ah yes, my bad I didn’t notice the viewers bit however it did mention about including those in the queue as well.
There is a bit in Eurogamer about 1 million being those who entered the world which wouldn’t, in my mind, include those who were in the queue. However we still don’t objectively know how many people played SL on launch day or for the few weeks afterwards nor do we have figures for the launch days of the other big MMOs; GW2, SWToR etc so it is a stretch to say how big it was in comparison.