Karl,
I'm not sure you're actually interested in an argument in favor of Slumdog. The Oscars are in the end a popularity contest. The membership is very diverse as are their artistic tastes and experience. Obviously you disagree with it winning, but what none of us can disagree with its the effects the cinematography had on the voters because they have made their opinion clear. I believe they voted that way because they found the cinematography fresh, inventive and very effective at immersing the audience in the story. If you want some specific example of that I would cite the following.
Overall image Quality or "look".
The higher contrast , higher saturation slightly noisier texture made the most of the environment. It was not the most realistic but complemented the editing style well by making colors stand out more and noticeable in the quick cutting sequences. It also allowed more color to show up reflected in the skin of the actors , which i think made them part of the environment more.
Scene when the Muslims and Hindus clash and our 2 your young heros run through the slums.
A great use of a tiny camera to be able to run with them in a real location with limited support. We really feel we are with them instead of watching at a distance. Great use of the short burst steprinted images shot with the DSLR. I can tell you first hand how difficult it is to shoot in India, and the way they chose to shoot got them amazing results that lesser filmmakers would have never achieved.
Use of wide lenses in Close ups.
Deliberate choice. Again consistent with an immersive style. Loved the scene when his brother shoots the Pimp.
2 Brothers talk at the Construction site. Who doesn't remember the city reflected in the Brothers glasses? Denying us access to his eyes is one thing, their old neighbor hood as the only thing we can see is something else.
I think Chris Menges work on The Reader was outstanding as usual. But the Academy Members remembered Slumdog more.
I personally don't think there is only one BEST every year.