I also have something called Glados instructing me through life now. A robotic female voice that insults me... I'm sure her advice is sound.
I am quite positive she shall most certainly make sure you are still alive near the end of such a strenuous voyage.
There actually is a cake room. Okay, as far as I can tell from the videos it is only accessable by hacks or glitches. Apparently an Easter Egg that they didn't quite finish or hid a bit too well. Spoiler: cake video [video=youtube;cvTNoKQBkwg]http://www.youtube.com/watch?v=cvTNoKQBkwg[/video]