Anyone advocating native desktop development is doing so because:
The app is high bendwidth/large datasets/computationally intensive (image/video/3d/statistics/games)
The developer feels at home with desktop development (hammer, nails, etc.).
I cannot believe there are developers who would recommend with straight face access-style (LOB) apps today.
That's not to say that it's easy to develop web apps. But that there isn't a choice. See what John Papa is doing these days (after being Silverlight evangelist).
BS. I can give you hundreds of reasons I advocate "native" desktop development (don't like the term native here, as it usually indicates natively compiled binaries, and I could care less about that aspect, what we really mean here is anything other than a "web app"). One of the most intelligent arguments I've ever seen comes from this web page:
The biggest reason to not care for web app development isn't even technical... users prefer native applications intuitively. I've talked to many such users and they can give you all sorts of reasons that might cause you to think there's a technical remedy to their specific complaint, but the reality is all of these complaints come down the levels of interaction that Matt talks about, and there's no technical fix here.