I worked from home one day last week (an unusual event for me at the moment) connecting to work through a VPN. I created a desktop shortcut to an application on the server.

After several restarts and log-on/off cycles the desktop shortcut was still there (without me having reconnected to the VPN). I eventually deleted the shortcut manually.

So, as evildictaitor said, it looks like Win7 is smart enough to keep shortcuts to networked resources.