Cryptic Messages from Microsoft on Halo 3

Could this be another viral marketing campaign or is it merely an interesting way to build hype for the upcoming single player story of Microsoft’s blockbuster Halo 3? Either way, the email I received today with this cryptic treatise feels like a step in the right direction for a game series that let me down at the end of its last campaign installment. Here is the text of the message:

HISTORY CIRCLING
BACK UPON US.

The gears of the Universe spin further
and further apart.
Ever greater grows the gulf between souls,
And distance gives false hope of safety
But for the grim tidings this messenger bears:

The enemy is almost upon us

Closing in from all sides,
Moving faster than the light
it snuffs with its passage,
Time echoes with the news of destruction.
History winding back upon itself.

Waves of an army march this way in unison,
Suffering and corruption are its battle cries.
For I have known this darkness
and felt its embrace once before-
Horror best laid to rest

Yet a Journey must commence

Look for the signs, the keepers of the flame.
They will lead you to war, and perhaps, to victory.

Interesting teaser or vague marketing doublespeak? Who are the keepers of the flame? Which enemy are they speaking of the Covenant or Spartans? I guess we’ll have to wait and see.