“OS X Lion’s set to ship around mid-July, but Apple’s recently-released 10.6.8 software update will upset many users, as it’s messing around with some AirPort wireless networks,” Jonny Evans reports for Computerworld.
“My own wireless set-up’s has been impacted by the problem, which manifested itself shortly after an upgrade to the new OS. One moment my Macs were online, the next they weren’t,” Evans reports. “A trawl through Apple’s support forums shows others are also affected.”
Evans reports, “iOS devices seem unaffected (though I’ve not tested the Apple TV). This implies that there’s nothing wrong with the network and that the problem affects only the Macs, and only those running the latest OS.”
Full article with some suggestions that may help if you’re affected here.