What are France, the UK, Germany and Italy doing in the G8?

This is one of the follow up posts to yesterday's post Key factors of "strength" in "post Doha" (and post WTO?) world systemics and on the occasion of the G8 meeting in Deauville (France), today and tomorrow.

The G8 started as G6 in the 1970s with France, Germany, Italy, Japan, the UK and the United States ie 4 large and "rich" (GDPwise) European countries members of the then EEC plus USA and Japan (also large and rich, see yesterday's post). Canada was invited later, and later Russia.
The EU is an extra, "associate" type of, participant.

My observations and points:

1) With G20 now in existence, what is G8 for?

2) Since the EEC is EU (since the 1990s) what is the point/sense of having France, Germany, Italy and the UK?

3) Considering Canada's population size compared to the other 7, why is it there (plus China and Brazil are in 2010 GDP terms richer than Canada)

4) Why is China (No. 1 in population and No. 2 in GDP) not there?

5) India is marginally less rich than Canada and Russia (1.4 vs 1.6 and 1.6 trillion USD 2010 see yesterday's article).

Hence, and depending of the weigt attached to GDP and population, the G8 should be:

either

A) G4: EU, USA, China and Japan

or

B) G7: EU, USA, China, Japan, India, Russia; plus Brazil (or the UNASUR).

The current G8 seems so 20th century and so globally irrelevant to 2011!

And in any case, EU members states have no place there, the EU does.

See also: Key factors of "strength" in "post Doha" (and post WTO?) world systemics