So I unfortunately have been gaming with a group that doesn't particularly like my favorite game (SR duH!) so I have been out of the loop from 2ed till just now getting most of the 4ed library so I wonder is there a repository that can spellout the end of 2ed all the way up to 4ed as far as the cannon metaplots? Is there one place to go to and say OH! this is what is happening?

First idea there is a whole load of canon fluff at the start of the 4e book covering the History of SR same as in earlier editions, it may not incorporate all the campaigns listed for every edition but it gives you a good grounding point.

Cool I was hoping that there was basically a wiki out there like everyone else in the world is putting up these days, something similar in scope to like the lost wiki. Where the plans of the dragons were and the cannon outcome, company moves and cannon outcome... all that sort of thing. But hey maybe they didn't have that stuff actually printed so I will be cool in not knowing any of it. I am trying to catch up with all the fluff in the 4ed book, just wondering if there was a lot of stuff I missed in 3ed that I should have to really catch up in the new ed!

Shadowrun timeline.

The Sixth World Wiki is an oft overlooked resource,
but it's exactly what you're looking for.

I'm pretty sure we don't use cannons anymore.
The word you're looking for is canon (isn't English awesome?).

Panther Assault CANNON. Accept no substitute.