Here's something rather strange I experience with the Acer Aspire One on OpenSUSE 11.1. I use the netinstall from a USB flash drive to install and try the KDE and Gnome version (On two different installs).

Networking from the ethernet port works fine, up until I enable network manager. As soon as I do this no networking works at all.

No Wireless Networks are displayed.
Wired network doesn't work and everything goes into offline mode, Firefox for example.

As soon as I switch back to ifup then I can use the Wired ethernet, however I cannot have this as a suitable solution as the Aspire is not mine and I'm setting it up for someone else who really needs to have Network manager working for easy connection to a wireless network.