First of all, let me say that I completely agree that the Air is in a class of it's own. However, for me the reason for that is down to it's style and slim form factor. Remember that it does have compromises.
Whilst the Air is clearly well suited to your personal requirements, it won't suit everyone's. There are plenty of people out there who simply won't consider the Air. There are plenty of people for whom the Air is the obvious, or even perhaps the ONLY choice.
However, I would suggest that there are far more people out there who just haven't made up their minds yet. For those people, the comparison threads are a valuable resource for seeing what else is on the market which may suit their personal needs and requirements.
It's also a natural instinct to see what else is available. This is in part to draw objective conclusions, and in part to satisfy oneself that the Air is in fact the right choice.
For the record, I bought an Air the moment I laid eyes on it. It suits my requirements 90% of the time. For the remainder, I can work around the compromises.
But, I'm still interested in seeing comparisons.
Just my humble opinion.