I just skimmed it, but there are a few problems with it. For example, at one point it say that in 2525 the human population reached 30 billion, but at another it says that the population of Earth is 5 billion and the population of it colonies is 1 billion.  Wouldn't that mean that 5/6 of the human population doesn't live on Earth or its colonies?

Also:

"Conduits are oppressed by the Mars Alliance and Helghast empire. By 2525, however, earth and E.D.N. hold large conduit populations. On E.D.N. III, forty percent of the population outside the Helghast territory is conduit. Sixty percent of earth's total population is Conduit. The number is high probably due to the fact that interracial marriage is highly romanticized by artists and story writers."  and "2525: Human-Covenant war. Covenant discovers and claims war on the Council. All ties between the Council and the Mars Alliance are broken. (HALO/KILLZONE/MASS EFFECT/)"

So, humans go to war with the Covenant, but they use no conduits or Helgast troops?