I played through the campaigns of all the games but ODST and Reach, but Halos 1-4 were very on rails and you only get a small glimpse of a much larger picture. I didn't realize the books expanded this much on the lore. I definitely want to read through them all but I have to finish AFFC/ADWD and the last 2 witcher books before I pickup anything else.
EDIT: Another thing is that I'm not sure where exactly the neogaf thread is getting all the info, if its just solely from the books or if the new terminals they added in MCC expanded more on everything. If I get my $400 bonus next month I might spend it on a Xbone and MCC.