Our wifi has two broadcast modes.. 5ghz and 2ghz.
If I’m on the 2ghz network, I get 10-20% packet loss and huge 500ms-2000ms latency.
I switched to the 5ghz network and I’m not having these issues. I’m not looking into this issue any further, but if you happen to be on a dual band router experiencing sudden network sluggishness on OSX Lion, try another wifi signal.
Yuji Tomita 