I'm using a relatively recent Centrino wireless card and I often experience periods of decreased connectivity, or (much more rarely) brief periods of no connectivity, as measured by pinging my wireless router. During the periods of decreased connectivity, I get about 20% packet loss. I filed a downstream bug report ( https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1002008 ) and was instructed to file a report here.

Tricky to reproduce, things just slow down when I'm using the internet, then I ping the wireless router and get around %20 packet loss. It does happen somewhat frequently.

In order to test a more recent kernel, I installed the 3.4 mainline kernel using the deb packages provided by Ubuntu here: http://kernel.ubuntu.com/~kernel-ppa/mainline/v3.4-precise/

Some additional information may be found at the downstream bug report mentioned above.