I agree for most people, though I feel like I'm pretty quick with Markdown + Pandoc -> LaTeX.
Definitely agree with the citations stuff though; Pandoc's BibTeX support is generally good, and I've had substantially fewer headaches with it than trying to get the reference stuff in MSWord to work.
I've worked in the book publishing industry and I've typeset books both using QuarkXPress (now everybody moved on to InDesign) and LaTeX. Using Word to typeset a book is a major PITA. Nobody in the professional book publishing industry is using Word to typeset books (well, ok, maybe 0.1% of masochists out there).
Word is convenient to quickly edit crappy looking documents: it's a document editor. It's not a typesetting program.
Weirdly enough I know someone with a book published by a big programming book company, and they accept manuscripts in Word only.
For books and similar long docs: Definitely LaTeX (preferably with Emacs org-mode), because Word has a way of f[oul]ing up automatic cross-references even in short documents; pandoc can then turn the LaTeX into whatever other format you want.