After reading your list again, however, this might just fall under "do they have a real reason to be present," although I think that could be two-fold, either for story development and for utility."
And to comment on the general.. commentship of this story: Colossus is definitely one of the standards of excellence with regards to interactive storytelling. I think the power of games to conflict the user (in the head) with multiple perspectives is still incredibly understated. There's a wide range of capabilites, be it for learning about a topic, understanding a complex issue, or in this case just telling a great story.
What's amazing is that Colossus was released more than five years ago, and the vast majority of games still don't take advantage of what makes this medium different than others.
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That said, I'm curious as to what other perspectives there are to be offered? Siding with Wander or siding with the Colossi seem to be the only two. Did anybody else see it in a different way?"
Great interview, great comments afterwards as well: http://www.gamasutra.com/view/feature/6500/the_creative_intent_of_rage.php"
Are they simply following their track record of cash-ins? Can anybody who's played Prototype give some input on whether that claim has any validity?"

Brian Eno did something unique with the Spore soundtrack. He used different loops that would come together randomly, and it created a really organic soundtrack. One of the most disappointing soundtrack moments was during the end of Mass Effect. Loved the music for the game, thought it worked really well with the themes, but then the credits roll and the badass song "M4 pt. II" by The Faunts comes on. Why was this saved for the credits???? Because there are lyrics? Take the plunge and do something cool with your sound, game developers."