Brent Simmons responds point by point to the misinformation in the Applelust.com article, “Going Native: The Attraction of the Cocoa Interface.”
Although the article is a mess, there are a couple of valid observations in it:
"Still, at this point in the evolution of Mac OS X, it is quite possible, as an end user, to perceive a very real difference between Cocoa and Carbon applications with respect to their interfaces and the way they interact with their users."
Sadly, I agree. I think one of the reasons is this: most Carbon developers still support Mac OS 9, which makes adopting X-only features (drawers, toolbars, and sheets) more difficult because of the need to maintain two separate pieces of code. But as more users move away from OS 9, Carbon developers will give their apps a good facelift and release X-only versions, possibly even Jaguar-only versions in some cases.