That's for another thread clearly...
Also, noisier than anything ever made ? I'm guessing you forgot the GeForce FX's cooler ?
Availability was already known to be pushed to April, so what's your point ? Also source on it "being planned to compete with dual-GPU part". Is it you guessing or was this ever confirmed ? As far as I remember, most rumors hinted at a dual GPU Fermi based card to be released as well, and that's the one that would take on the HD 5970. Given the power constraints, that certainly won't happen soon.
As for what exactly is better: performance. Most people here that just love to cite certain "articles", were expecting the GTX 480 to match or slightly outrun (5%) the HD 5870. That isn't the case. It's better and from a GPU that's not even fully enabled, given the problems it had. It was certainly a complicated birth
Now power is definitely an issue. It consumes way too much for its performance and that's what's certainly going to be tackled on the next iteration and derivatives.