Make it clear you've changed the /etc/network/interfaces

In Intrepid I wanted to browse for wireless networks but I wasn't able to find it anywhere.
Through the System->Preferences->Network Configuration I was able to add a wireless network by SSID, but that didn't actually work, nor seemed to be very user friendly anyway. All I could do, was see was the signal strength of my ath0 device. That's it.

Googling for this issue was pretty hard, and for all I knew, the network applet was seriously damaged after my upgrade from Hardy.

Finally it turned out: I had some entries in my /etc/network/interfaces file and needed to clear that file. After that, everything worked beautifully (more power to you).

While this may all be very logical (I can imagine network-manager not tempering with custom interfaces, that's probably a good thing), it would have been very helpful if there was a clue about this in the user interface. Maybe a lightbulb saying:

"A custom configuration file is disabling network-manager, please clear /etc/network/interfaces if you want all features enabled"

or something like that - would be a simple way of making Ubuntu more user friendly, and saving some frustration. In my humble opinion, that is. Please consider.

Other than that, thanks for all of your hard work, and making Ubuntu such a great OS.