This is actually true, look at the top right corner: http://i3.minus.com/ibgZEIGf9waQti.png It's about the same for the other maps.
It could be different now though, since that's about a year and a half old. When you had to use /red and /blue to join I think more people might have always joined red because it was shorter, causing red to have more people on average.
It could be different now though, since that's about a year and a half old. When you had to use /red and /blue to join I think more people might have always joined red because it was shorter, causing red to have more people on average.