What is the function of 127.0.1.1 in /etc/hosts

What purpose does 127.0.1.1 serve in /etc/hosts besides 127.0.0.1?
I posted the question to the Debian social group in this thread.
I remember seeing references to it being needed for gnome, but does it? Really? I've been using gnome without it for ages. No hill-behavior perceived.
I went on and asked a search engine about it and here's what I found:
The search engine pointed me to read the Debian reference which pointed to a Debian bug #719621 in debian-reference package which, in turn, pointed to Debian bug #316099 in netcfg package...
Well, it does mention that it is needed for software (they specifically mention GNOME) that expect to find resources on the local machine but have no permanent internet connection and might not be able to resolve the host name (actually, they can't resolve the IP address, it seems). Since local services actually listen to all 127.0.0.0/8 range, trying to connect to 127.0.1.1 will succeed.
I am still confused about all this, maybe because I've been living without that line in /etc/hosts with no perceived misbehavior.