Why are there so many ways to start and stop services

There are a few methods I know of

old method (sysvinit):
$sudo /etc/init.d/something start

new? method (upstart)
$sudo service something start

new new method?
$sudo start something

In 11.10 this happens on all the machines I know:

$ sudo service networking restart
restart: Unknown instance:

I'm trying to figure out what is going on because traditional tools such as rcconf and sysv-rc-conf don't seem to work anymore. There is a file /etc/init.d/networking that says it's not the right way to restart networking. So I'm confused. The documentation page https://help.ubuntu.com/11.10/serverguide/C/index.html doesn't talk about this at all.

Is there a document that describes how these services start? What is the method to this madness.

Thanks
-J