@bundo,
It's not always empty. But:
1) Time difference between Europe and America.
2) The chat has been hidden well only accessible by clicking the MSN Messenger like icon. I'm sure this scare some people away.
3) People don't care about it
4) Most people are only on this forum about 10~20 minutes, most of the time arguing with each other.
5) Nothing really interesting gets said on the chat that can't be said on the forum.
6) Should i go on?