, 20111004 * Determine that normative RFC 2119 terms (MUST, SHOULD, MAY, etc.) are truly intended in all cases where capitalized. * Document hierarchy WRT headings has a flaw, in that topics related to animated WebPs are discussed under subheads of "Single-image WebP Files". * Several passages could be made clearer. * Overall edit for scope. Portions are phrased as an introduction to the 0.1.3 RIFF container additions, rather than a holistic guide to WebP. * To wit, suggest s/[spec|specification]/guide/g . "Spec" can imply a standards track; in any case it's too formal for a work in progress. * Sections and passages re "multi-image" should likely be suppressed until multi-image drops. * Improve the term "Mux-Container".