You can also read some responses at Game Politics ... (their article mostly recapitulates the Kotatku story, but the reader comments are interesting).

Oops, I guess we're stripping html these days from comments. The Game Politics story is here: http://gamepolitics.com/2007/01/05/sponsor-threats-force-removal-of-super-columbine-game-from-slamdance-festival-competition/

Wow, this is terrible. I'm sure the festival organizers, including Sam Roberts, whom Ian and met last year when we competed there, are devastated by being forced into this. They courted SCMRPG! for the festival, but in hindsight, it was a little too risky. Sam is a good guy who wants to push on the frontiers of gaming; he must be very disappointed. But he and the other organizers should be proud they had the guts to originally include it in the festival, I hope people realize it was against their wishes to pull it. It would have been unfair to the other finalists to have not pulled it, leading to the festival being cancelled.

It's unclear how much this will tarnish the reputation of Slamdance, or the broader game industry somehow, but hopefully this event will lead to more debate and discussion about games as a medium for serious expression. Although school shootings are a very incendiary topic, I think it's a better tool for debate than, say, the more puerile controversies over the right to have prostitutes and hidden soft-core sex in the Grand Theft Auto games.

I also recommend everyone rent Elephant, if you haven't already — a movie on the same topic as SCMRPG!, which won the top prize at film's most prestigious festival, for crissakes! The irony is thick here.
http://www.cbsnews.com/stories/2003/05/21/entertainment/cannes/main554985.shtml

For those like me who aren’t sure they can stomach actually playing the game, but want to know what it’s about artistically, here’s a really good review with some spoilers at the end.

http://tinyurl.com/ye5nkl

(By the way, while I don't feel up to playing the game myself, I agree that this decision sucks.)