Do you mean wireless connections or additional physical connections? Because the former won't show up in the drop down if they are not in range.

I meant access points. Essentially the same thing that the delete button on the wireless tab in nm-connection-editor does. But the bigger problem here is that we fail to give any access to stored, out-of-range access points at all.

On top of being able to "delete" networks, I would really like being able to disable autoconnection to some of them (like I could do in networkmanager 0.8.x); otherwise, if you connect to one of those "linksys" or "free wifi" networks once, your computer will try to connect to every instance of them everytime they are in range.

Should this be considered part of this bug, or should I file another?

Let me give an example. I have many wifi networks in range near me when i am at home (which is a good portion of my computer useage). I've usually use dannyswifi, but i've for some reason, whether by accident or intention, one day tried connecting to alternativewifi. It failed. 

Now, every single time i boot or wake up my laptop, it always tries connecting to alternatewifi first. Multiple times a day, i have to tell it to cancel, and there's no way to tell it to not bother trying. 

Incredibly annoying bug.

I have the same problem described by Danny.

My workplace has improved its wireless networking: they have created a new network that requires no web proxy, while the old network remains and still requires a web proxy.

Often when I boot or wake up my laptop, it connects first to the old network. Typically this occurs when I go to show something to a colleague or superior. I am left flustered as I scramble to diagnose this.

This is a significant usability problem for me.

*** Bug 658885 has been marked as a duplicate of this bug. ***

*** Bug 662733 has been marked as a duplicate of this bug. ***

This is fixed in GNOME 3.4.