Okay a couple of comments on this ultra-nerd discussion:
Looking at the evidence in Portal I'm pretty willing to accept that GlaDOS killed all those people. I don't think there is any doubt about that. Indeed looking at some of the dirctor's comments about the red phone with the cut cord and such (a safety protocol for just this kind of thing that failed) it's pretty obvious that there was a crisis, and that what's more people knew what was going on as it happened since they tried to stop it and even install that morality core thing which apparently had no effect.
The big question to me here was whether or not GlaDOS killed all of the AS people or not. I am guessing going by the epilogue/song that the case is 'no'. I'm thinking AS was ultimatly running an experiment. Perhaps to test GlaDOS as a weapon by assigning "her" to kill all of the people they sent to the building, and to see if anyone could defeat the AI or if it had been perfected. "Bring Your Daughter To Work" day could very well have been a way of simply obtaining more targets, as well as creating a sense of jeopardy for the scentists in the building to try even harder to stop the AI as if it was combat conditions.
Thus there might very well be a board of directors (and perhaps a certain infamously insane CEO) in the backround somewhere whom GlaDOS is answering to. The lyrics making it clear that not only was GlaDOS not killed, but that "she" is still developing more science both doing tests on, and working in the intrests of those who are still alive (seemingly implied as two seperate groups).
How it all ties together is a big unknown, however my gut feeling has sort of been along the lines of AS killing it's own people. Either that or given the legendary insanity of the AS founder (backround about his 'take a wish' foundation and such) and his goverment backing due to the basic portal technology, that perhaps the goverment tampered with GlaDOS (which was pimped to differant groups for things like a sewer management program, that doubled as a disk operating system or whatever) to basically wipe out AS and get direct control of the technology.
Of course no theory works perfectly given the obvious condition of the world. The only ones who know for sure, are of course Valve. It's quite possible (very probable for that matter) that they never came up with a clear answer themselves, and will be making it up as they go along for the sequel. The apparent depth disguising the fact that it was never created with an answer in mind given the experimental nature of the game (which was a smashing success).
For example I was reading that the whole "cake" thing started when Valve were wondering what kind of underlying philsophy they should write into the game, and after a bit of silence someone mentioned "well a lot of people like cake". If that story is true, it does imply that they were probably winging a lot of it, and figured that if the game existed people like me would go off on tangents like this one, and give them ideas on how to answer all the questions based on trying to guess what they were thinking.
>>>----Therumancer--->