I tried to join some AU only games last night (first MP game). The US guys wouldn't let me play due to my ping. When I did get into a game, I didn't even see 2 of the other guys in my connection info - but I could see them in the lobby. I have my ports open (6073UDP and 6100-6200UDP), forwarded those ports and ran the impulsereactoroptions program and set the range to use to 6100-6200. Turning off the firewall didn't work.
As stated above, it is hard enough to get a game in Australia (playing Sins after work = no one on as they are all asleep). There needs to be a diagnostic tool for helping people work out what is wrong with their connection info.