Here is an interesting comparison of Cortana over the course of the 4 halo games:
PTesh adds his dulcet prepubescent tones over the top of one of the new trailers for weapons...
Try upgrading your browser to Google chrome (you wont regret it). There is probably an IE...
Marathon Logo on Assault Carrier
Level: Crow's Nest
In the part of the level where you have to defend the 2 (or 3) phantoms that drop off the covenant (you do this 2 times) you can pause go into theater and freecam out the exit of the building, go to the Assault Carrier and look at where the banshees are coming out of, you'll see a Marathon logo.