I have friends in both Sydney and Alice Springs who've had none to constant complaints about their pings to US gaming servers (MechCommander through WoW).
Just based on a couple of traceroutes I just did, here's the latency for me:
my isp: 29 ms
west coast (las): 85-90 ms
sydney: 240 ms
melbourne: 255 ms
adelaide: 270 ms
alice springs: 290-300 ms
Things are a lot better than they were 10 years ago on sheer latency. I suspect that fatness of the pipes may still be an issue. From speed test sites, I've noticed my downloads from Australian servers are around 330 kbps while the ones to US West Coast servers is around 5-6 mbps. My connection to servers in the Northeast is 15-25 mbps.
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