I really like that I can have the source file broken up over several lines but that it still defines a semantic "paragraph" that is rendered properly when convert to HTML or Latex.

If it respected single newlines, then I'd feel compelled to avoid newlines, but I'm trained too strongly on respecting column-formatted text files (though I don't stick religiously to the 72 or 80 char limit), so this would be a problem for me.