I think a lot of this is setting the stage for future content honestly. The bigger focus this time around seemed to be the Vex, as the Raid is going to involve them as well.

I think the harder to find grimoire cards actually tell more story bits than the regular ones. Find the dead ghosts if you can for more of that, or wait till we start discussing them here.

http://destiny.bungie.org/forum/index.php?id=34699

I agree with the other guys though. Looks like they are setting up for more stuff to happen later. Just too bad we couldn't see it this game.

One thing to check in particular is the Activities section in the Grimoire. There are follow ups and reactions from the City to the things you are doing. For instance, about Rasputin it says:

They say the Warminds were a legend, even in their own time. Now we know Rasputin lives. You discovery is priceless, Guardian. Nothing in the Cosmodrome is more important. - Ikora Rey

For The Last Array we get:

The Terrestial Array was Dead Orbit's hope to reconnect to the lost colonies of our inner system. You succeeded where they failed. Though Rasputin seized control of the Array, that only strengthens our resolve to break the old Warmind's firewalls and enlist its help in the wars to come. We must reach Rasputin, and make our case. - Commander Zavala

It seems there is story being told through the Grimoire. If you put it all together it comes out something like this:

• Rasputin was the Warmind to see The Darkness coming.
  
• He sounded the alarm, of a "Skyshock" event, and even recognized that this wasn't just an alien invasion or incoming war but it was potentially an extinction level conflict or enemy.
  
• He made moves to rally Humanity's forces and secure The Traveler from the enemy.
  
• He somehow survived the battle with The Darkness where most of Humanity was killed and has been hold up in Old Russia for centuries. Perhaps damaged? Perhaps biding his time?
  
• The Fallen seem to have partially dug him out and tried to hack him but one Guardian.... YOU... stopped them and connected Rasputin to the communications array.
  
• Presumably, being able to transmit to the inner colonies and any other intelligences that survived will be important. There is a second Warmind on Mars that we know of who is part of one of the Mars Strikes so who knows what's that will be about.

Alright guys first of am enjoying the game for the most part. My real problem is the story.

After beating the game I'm kind of clueless on what we have actually done and how it effects things. I had a few questions that been bugging me and I don't know if I missed something or what.

First off The Warmind, what is the point or his deal. We did a mission find out he is alive and that's it. What the heck is it for? I remember it being mentioned on mars but like what was the point of finding him what did it gain us and how is it even relevant to the story?

Second what is the deal with the Black Garden and why was it so important to Destory it? I mean did we destroy it I know I killed a boss there and stopped the vex from wiping out earth?

Mentioned in the Grimoire cards is the fact that the being you destroy at the end is some form of god-like entity similar in function to the Traveler, but serving the Darkness instead. Take that for what you will. I simply saw it as indication that there are much stronger forces starting to come into play.