Here's a list of contributors to PmWiki development and improvement. My apologies if I've forgotten anyone -- feel free to add your name if you've been left out, feel free to remove your name if you don't want to be associated with these people. :-)
GNUZoo - Several recipes, some security and bug fixes
Scott Duff - pmwe, simple-journal.php, all-around Pm sanity checker
Ross Kowalski - uploads and printable page research
John Rankin - WikiTrails, Links, EditQuickReference, notify.php, documentation, debugging
Joachim Durchholz - hacking documentation, general pest
Jessica Tishmack - uploads, testing
Jean-Claude Gorichon - voting
Janice Heinold - early PmWiki testing and suggestions, documentation
James Davis - WikiStyles markup, testing
Isabelle Michaud - floating images markup, Wiki Groups, uploads/attachments
Carlo Strozzi - Internationalization, PmWiki on Boa, HTML redirection
Michael Weiner - Modifications to the ToDo, RssFeedDisplay, MyPmWiki, and CommentBox recipes
Criss Ittermann (aka Crisses/XES) - ye old best seller Blocklist2 that topped the charts for a while and many other recipes
Rev. Ian MacGregor - I've contributed with monetary donations, skins, bug reports and continued testing. My personal website(approuver les sites) is powered by PmWiki.
Petko Yotov - I have been the PmWiki core developer and pmwiki.org webmaster since January 2009 (after having worked with it since 2004). My contributions are at the Change log page, in the PITS issue tracking system and in the mailing lists. My cookbook recipes can be found at my profile page.