HN is probably the wrong audience because windows and filesystems are uniquely well suited abstractions for developers who have umpteen workflows and use cases of significant complexity. However observing how huge an improvement an iPad is for my joe-sixpack relatives, I think it's worth exploring the idea of how far can iOS can be taken by power users. I certainly think it could feasibly meet the needs of specific creative professionals like writers, designers or video editors.
Lighter. Longer lasting battery. Dead easy app management. No "blue screens". Apps designed for direct manipulation. No configuration and maintenance hassle or sys-adminy stuff. Works great on a desk, on your lap, on a sofa, on the bed.
But best of all: if you're a writer/journalist/etc, and mostly do writing, web, email, reading, IM, etc, it does all you need, and nothing you don't.