I just did a big update of the SMW quick reference ("cheat sheet"). It's now two pages, instead of one, because the amount of information well exceeded what could be fit onto one page (actually, two pages seems like big fairly enough now). In addition to information on Semantic MediaWiki, Semantic Forms, Semantic Result Formats and Semantic Gallery, the page now contains data on Semantic Drilldown, Semantic Internal Objects, Semantic Compound Queries and External Data. And information on LocalSettings.php settings for many of the extensions has been added.
You can see the new version here, in PDF and PNG form: