> You can drive it from command line using cnetworkmanager...
You can't manage wireless connections through it (adding, removing, etc.). Only nm-applet supports it. You could hack the XML config files I suppose, but wpa_supplicant.conf is easier in that case (except the root requirement, but to avoid XML and a session dbus for just one app, I'll take it).
> I'm not sure I remember the time when I was last forced to think about the fact that I have different SSIDs at home and at work, etc.
wpa_supplicant.conf allows you to do the same. The priority= setting allows it to choose in the face of choice as well. I don't recall NM having that last I used it.
The only practical difference between NM and wpa_supplicant in my experience is that NM will connect and drop automatically where I need to do "ifup" manually. However, where NM will drop at a network disruption, ifup will stay up until I take it down. That, IMO, is well worth the slight inconvenience of an ifup at boot (which is in the history right alongside exec startx).