My testing of the 20120927 Waldorf builds has been excellent so far except for a bug in ath5k kernel module that renders my old Atheros AR2413 card next to useless. It connects ok but then browsing quickly begins to slow and is virtually unusable. Anyhow, here is a quick work around for the AR2413 card that may work for other Atheros cards if you are having the same problem.
Create a new file in etc/modprobe.d called modprobe.conf (substitute your favourite text editor if not geany)
sudo geany /etc/modprobe.d/modprobe.conf
add this line then save and exit.
options ath5k nohwcrypt
If you know how to unload the ath5k module, reload and power down and up your network then do so at this stage. I find it's easier to just reboot
I am using an EEE 1000HE with CrunchBang 10 and I was experiencing the same probloms as you. This seems to have fixed it. Fingers crossed that this fix will hold! Thank you!