I'm preparing to "follow" these directions
which will make VirtualBox's networking behave like VMWare's "NAT" networking. Of course, these instructions are for a Ubuntu/Debian setup.
I am quite certain that I can write a script that'll do the equivalent steps on my Fedora 11 box -- which is acceptable to me. I would, however, like to know how to splice this stuff into NetworkManager and/or /etc/sysconfig/networking/devices/, to do this the "right" way.
The desired networking behavior:
* VM's get assigned addresses via DHCP on a virtual network
* VM's can talk to each other and to their physical host
* VM traffic out to the 'real world' is NATted