Q: How often/quickly is the official Emacs manual updated?
The release announcement of Emacs 24.4 has a blurb at the bottom stating that the FSF's official Emacs manual has been updated to correspond to version 24.2. It also notes that buying the manual is a good way to support the FSF's work.
Roughly speaking, how frequently is the manual updated (in terms of dates and/or Emacs versions)? I'd be happy to throw some money the FSF's way on this, but I'd be less happy if the manual were updated to, say, version 24.4 a month after I bought a copy of this version.
UPDATE: The plot thickens. The paper copy available from the FSF store corresponds to Emacs version 24.2. Yet there is also an updated PDF version of the manual that corresponds to Emacs version 24.4. (Oddly enough, it's about 40 pages shorter than the 24.2 version.)