Science Fair Poster 4 (Spoiler)
I asked this question to, and the answer is: the developers. The change in the elevator rooms and the changes to the original test chambers are retcons, since there was more than a handful of them working on this project this go around.
I would have thought it would have been among some stuff she made whilst Chell was escaping, then replicated once GLaDOS was back online.
Either that or a wizard did it.
http://www.soundcloud.com/jomonay
"Anything that you do, just be THE best at it" - Kanye West
Even if 50000 years have passed, at the end when Chell is ejected from Aperture, you see wheat fields. That implies some sort of civilization, so humans (or at least some sort of civilization) are around in some form.
That form of civilization can range from something 5000 years ago to a few hundred years in the future.
That form of civilization can range from something 5000 years ago to a few hundred years in the future.
if you watch the light bridge videos you'll see they get the light harvested from
so since that means she's technically still on aperture property we still don't know what has become of the world.
Also just a note for the "9999.. 9" people, if you extract that sound file you'll find that it is quite a lot longer, they just cut it short in-game. There's actually a whole speech by the "announcer". The "999" goes on through the whole sound file, which is pretty long. I'd guess twenty or more nines.
~Sidneys1
^Click to go to my Steam Community Profile^
~Sidneys1
55. I counted. 
They probably would have kept going too if the sound file didn't have to end.
If she was sleeping for that many days... she would have been sleeping for 2,73972603 ? 10/51 dimension.
also.. I just recently re-beat the game (while going through all the commentary.) and.. the wheat fields we see are not harvested wheat fields (as far as i can tell). In that, There are no rows... Farmers, who are farming for food, typically put everything in rows. these have none.
I've never farmed wheat, so I could be wrong on this, but I imagine it's similar to anything else i've ever delt with. So, we don't really know if this is an actual crop, or just wild wheat growing.