Hi,
External USB is broken for me: no external drive is ever detected (I tried 3 different) in either kernel. I also had the Pandora corrupt my nand (can't boot anymore and will have to reflash firware) when attemting to go to power saving mode with AAAA running (the pandora got stuck and I had to force it off by removing the battery).
AFAIK you have to run some command line to enable the USB, its not broken just not enabled. again, if i recall correctly this was to help with power saving. A quick search around for enabling external wifi will help you find the topic i think
comands for enabling/disabling usb host in this post: