Quote Originally Posted by Raikki View Post
Expanding upon this, here are some pings to that IP (24.105.62.129, Blizzard US Central in Chicago) from backbone servers in various locations:

Portland, OR: 49ms (Northwest US)
San Diego, CA: 54ms (Southwest US)
Boston, MA: 24ms (Northeast US)
Miami, FL: 33ms (Southeast US)
Frankfurt, Germany: 109ms

Residential pings will be a bit higher obviously and may not have as good routes as these. Hopefully it's obvious that not only would a huge percentage of North Americans be getting stellar latency, but the impact on European players may have been reduced significantly enough to allow them to stay on their preferred server.
People saying "100ms is good" just show their ignorance of other online games, really. There's a reason so many other games place their NA servers centrally or run several server locations across the continent.