ya, you have to go into your bedroom and use eagle vision (Y) to look at the wall to roll the credits. but what its getting at is that your character has learned to use eagle vision, because his DNA is starting to run with the DNA of Altairs from the Animus. All of the writings are code, for what im not exactly sure but they just say certain things that clue you into other little things
WARNING: Major spoilers!! Link
Explains it all. I understood about 2/3 of it on my own. <_<