Dear administrators of pdfreaders.org ,
i find your site to be a great initiative to spread the use of free and open source alternatives to Adobe Reader for reading PDF files.
But i think that what for me is the best alternative for Mac OS X is missing on your list. I am referring to the Skim reader available at sourceforge on: http://skim-app.sourceforge.net/ The Skim app is especially useful when working with scientific documents or when generating PDFs from latex, since it has full pdfsync support. I do not know any other reader that implements the above characteristics in a suitable way.
Unfortunately, the Skim reader is only available for Mac. But i think it is a very needed addition to the pdfreaders.org site. And let's hope someone takes its source and makes version for windows and linux as well, then it will be totally perfect.
Regards,