Want to help out on the PHP project but not sure where to start? Lukas Smith suggests helping out with the wiki (at wiki.php.net).
I feel that I can make more of a difference in these other [personal] projects. [...] I hope others will pick up the slack and make sure that PDO gets love, at people diligently follow up on todo items mentioned on internals and that someone else picks up wiki.php.net and takes care of some regular maintenance stuff.
He mentions one thing specifically - an update that will need to happen to the Dokuwiki software the wiki runs on. If you're interested, send Lukas an email/leave a comment and he'll point you in the right direction.