Based on a few of the IF2010 reviews I’ve read, I gather it is considered polite for an IF game to respond to “About”. Is there any agreement or standard as to what should be provided in an about statement, and if so, how long it should be?
(The commonality of the word “about” is making it fairly difficult to search for an answer …)
The “about” command is one of the first things players try because they expect it to give them information about any quirks, special features or non-standard behavior of the game.
Some players, like Emily Short, also expect it to have the author’s details and a list of testers. Presumably if a game is released anonymously for a comp then the author details can wait until a post-comp update 
Some stories, in addition to noting unusual things, also contain a general guide to IF. I’m not sure if it’s the best place to put such a guide but it probably can’t hurt.
And if you make about and help/hint synonyms then it’s also a place to get in-game hints.
The things I expect to find when I type ABOUT:
Obviously, if you put all that information in a single block of text it might be a bit much. You can use a menu to break it up, or just tell me where else to find the info, e.g. “Type CREDITS to find out who brought you this fine piece of IF.” (And of course, not all of those items will be relevant to every game.)
To clarify here: my good-faith effort to find out about testers includes trying a whole bunch of commands – ABOUT, HELP, HINT, MENU, CREDITS, INFO. If none of those turn up anything, I start getting suspicious.
[ Late-night drunk-typing deleted. It was nothing terrible, or anything — just an off-topic ramble about not much, really. 87 ]