Including a separate readme.txt for ebook-convert containing all available options/permutations would be much appreciated while you're still working on the online manual. Besides, I think I'd much rather view the help file in my favorite text viewer/editor rather than in shell.
It doesn't even have to be pretty. I'm not sure how ebook-convert limits the options (by input format? output format? both?), but a readme containing the following would probably work well enough for most people:
	Code:
	
Syntax:
ebook-convert .....
General Options:
blah...             //output of ebook-convert --help
List of Supported Input Formats:
List of Supported Output Formats:
FORMAT-SPECIFIC OPTIONS
EPUB                //if options change based on output format
HTML to EPUB        //if options change based on both input and output formats
blah...             //output of ebook-convert file.html .epub --help
LRF                 //if options change based on output format
HTML to LRF         //if options change based on both input and output formats
blah...             //output of ebook-convert file.html .lrf --help
etc...
 I've made an MS-DOS batch file that creates something similar to the above for myself.
	Code:
	
@echo off
ebook-convert --help>ebook-convert-readme.txt
echo  >>ebook-convert-readme.txt
echo **********************>>ebook-convert-readme.txt
echo *                    *>>ebook-convert-readme.txt
echo *  EPUB (html2epub)  *>>ebook-convert-readme.txt
echo *                    *>>ebook-convert-readme.txt
echo **********************>>ebook-convert-readme.txt
ebook-convert file.html .epub --help>>ebook-convert-readme.txt
echo  >>ebook-convert-readme.txt
echo *******************>>ebook-convert-readme.txt
echo *                 *>>ebook-convert-readme.txt
echo *  LIT (any2lit)  *>>ebook-convert-readme.txt
echo *                 *>>ebook-convert-readme.txt
echo *******************>>ebook-convert-readme.txt
ebook-convert file.html .lit --help>>ebook-convert-readme.txt
echo  >>ebook-convert-readme.txt
echo *********************>>ebook-convert-readme.txt
echo *                   *>>ebook-convert-readme.txt
echo *  MOBI (any2mobi)  *>>ebook-convert-readme.txt
echo *                   *>>ebook-convert-readme.txt
echo *********************>>ebook-convert-readme.txt
ebook-convert file.html .mobi --help>>ebook-convert-readme.txt
echo  >>ebook-convert-readme.txt
echo ************************>>ebook-convert-readme.txt
echo *                      *>>ebook-convert-readme.txt
echo *  OEBPS (html2oebps)  *>>ebook-convert-readme.txt
echo *                      *>>ebook-convert-readme.txt
echo ************************>>ebook-convert-readme.txt
ebook-convert file.html folder --help>>ebook-convert-readme.txt
 My source files are primarily in HTML format and the ones in the batch file are the only formats I convert to. I also added the old names of the corresponding command-line utilities (at least the ones I used) for my convenience.