I've yet to find a task Pages/Numbers/Keynote can't do. Admittedly, I'm not a power user for this kind of work but I'd bet the vast majority of users aren't either.
I was wondering if this comment was intended to be sarcastic.
Otherwise, I am wondering what especially Pages
can do. Right now, the feature set only slightly exceeds Wordpad for Windows. Yes, it's good enough for writing a letter or creating some small brochure, but that's it. How do you handle a bigger document with Pages if you can't have headings/subheadings that you can see in a clickable document map? That for me is already the killer. And that is only the first of many features that I miss in Pages, as much as I want to love that software.
Pages '09 was not bad, but the current version is a toy. And no, that is not something that applies to a small group of power users. The majority of office users use it for business purposes. For them, Wordpad is not enough. Pages simply isn't usable in a professional environment, and I really wonder what Apple uses internally, because they certainly have to deal with long design documents. I strongly suspect that most Apple employees use Pages '09.
At least until recently, iCloud support was still an argument for iWork for me, until Pages on my iPhone decided to overwrite a document with a four-week-old version just like that (luckily Time Machine on the Mac recovered the newest version). That is when I stopped using iWork for good.