The video contains various images from the Halo universe and snippets of text from what is believed to be the ancient Forerunner race. From the clues gathered so far, I'm starting to believe this ARG is going to tell us some key information regarding the Forerunners and their horrible little science project, the Flood.

This video is just a dissected version of the first video. It slows down key parts to help reveal a better picture of what's going on.

The Hushed Casket has been doing a fantastic job staying up to date and finding out all the little bits and pieces. Other than the video, there are also a couple of pictures and text files the Hushed Casket was able to find. The first image is a close up of bacteria, possibly Flood. The second image shows the stars as well as the now famous glyph (I wonder how soon until someone gets a glyph tattoo). Here are the two text files:

Log5_Transcript:

THIS IS MY FINAL ENTRY, AND I AM LEFT WITH ONE HOPE
THAT ONE DAY, SOMEONE, ANYONE IS AROUND TO WITNESS THIS WARNING
{//}
KNOW THAT A THOUSAND OTHER PLANS WERE TRIED AND FAILED
{//}
KNOW THAT ENERGETIC AND TENACIOUS AS LIFE IS
IT HAS AN ANTITHESIS JUST AS POWERFUL
IT IS THAT THING THAT WE MUST OBLITERATE

Array_Recorder_Date:

Halo array –System Data Recorder

[<array-sdr.> 3 minutes 5 seconds]
{c-match-reconfirmed}. Sphere secure to .1889 of passing fleet. Offensive tactics confirmed.
Feint tactics in limited push.
<Array sync commence>
Sys//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////{online}
Index: {check}
{D-com} There is no peace left. No place where the parasite cannot reach. You were right about it
all. Let us hope the final measure is not too late.

[<array-sdr.> 1 minutes 12 seconds]
Confrm: Array burn radium {check} 3.0 
Confrm: Array sync …1…2…3…4…5…6…7…{check}
Commence…_{ }

[<array-sdr.> 60 seconds]
Commence…_{check}
Confrm: -00-00-00-59-0999-
{c-match-line-hold} acceptable losses confirmed
{D-com}  It's done. By my hands. The pyrrhic solution is ignited. All I have left is the quiet of
space to lull me to sleep. I will dream of you.

[<array-sdr.> 49 seconds]
Authorize  -00-00-00-48-0999-
Array Authorized…_ Array Authorized…_ Array Authorized…_ Array Authorized…_ Array
Authorized…_ Array Authorized…_ Array Authorized…_ Array Authorized…_ Array Authorized…_
Array Authorized…_ Array Authorized…_ Array Authorized…_ Array Authorized…_ Array
Authorized…_ Array Authorized…_{check}

[<array-sdr.> 23 seconds]
fire: -00-00-00-22-0999-
Confrm: wpnt {auth}
Core sequence <%>  <%>

[<array-sdr.> 11 seconds]
fire: -00-00-00-10-0999-
{c-match-burn} effectiveness of enemy core fleet negligible
{D-com} I feel no peril.

[<array-sdr.> 5 seconds]
fire: -00-00-00-04-0999-
<enter reversion sequence to deactivate>
{D-com} No pain. No remorse. Is that normal?


[<array-sdr.> 0 seconds]
fire: -00-00-00-00-0001-
Reversion Sequence…{negative}
Array Authorized…_{Activate}
Rings online…_{Activate}
<Fire> 

[<array-sdr.> 7 seconds]
+00+00+00+07+0001+
reset…………………………..
reset…………………………..
reset…………………………..
reset…………………………..
reset…………………………..
reset…………………………..
reset…………………………..
[Editor's note, this reset line repeats about 50 times.]

Obviously, until the other servers open up, we can only truly guess at what's going on. So what do you think the clues are leading up to?

[Thanks to Buck for the video links]