Tobi Oetiker has uploaded the latest version of his short introduction to LaTeX 2e, and I've installed it as requested, and updated the catalogue repository.
This new version of the introduction features a rework of the mathematics chapter (done by Lan Thuy Pham), which (among other things) assumes amsmath is loaded, in all its advice.
Thanks Tobi (and Pham) for the update.
Users may browse the catalogue entry (for what it's worth) at http://mirror.ctan.org/help/Catalogue/entries/lshort-english.html or browse the package directory at http://mirror.ctan.org/info/lshort/english/ Those who only want the document itself may retrieve http://mirror.ctan.org/info/lshort/english/lshort.pdf
The catalogue entry will be updated overnight, the package itself already being on its way around the world.
Robin Fairbairns
For the CTAN team