I'd like to announce that Jérôme Loyet stepped up this weekend and hacked up the first round of code to get dynamic process management going. Antony committed it (see below) and it's on its way to being part of PHP core as well. So two major events in only a week and a half or so!
See http://news.php.net/php.internals/46414.
Good job Jérôme. Where were you a couple months ago, buddy? 
Read it here: http://news.php.net/php.internals/46277.
First off, big thanks to Antony Dovgal. I've exchanged words with him in the past about PHP-FPM (and actually other PHP things) but was completely unaware he was working on this.
So, we've got a blessing but also an interesting dilemma on our hands. We've got a wishlist and some bugs to work out. I have a feeling if Antony updated some of the CGI internals it may have resolved some of those bugs. Not sure. I'm trying to get some specifics now - what version of PHP-FPM he brought in, how the community can still support it and how difficult it may be to submit patching, if he thinks a separate management daemon makes more sense than keeping it glued inside of the SAPI (it seems out of place to me for a SAPI to require a proprietary configuration file and daemon .pid, log, etc. files...)
Hopefully I can get ahold of him soon and discuss some of this. I was already mid-discussion with another PHP core developer about how they think the best approach would be to get PHP-FPM aligned with PHP core (they leaned more towards a separate SAPI too.)
My main goal is to make it easy as it can be for PHP-FPM to become an official package or included with PHP so that people who use PHP from repositories on their favorite distributions and such can enjoy the benefits of PHP-FPM without patches or separate downloads. If the management portion does split off, I fully intend on making sure it is aligned properly and is as simple as "apt-get install php5-fpm" or something of that nature. Still easily installed and everything.
Anyway, we'll see how things go. This caught me off guard and now I have to figure out at what point we're at now with development. Jérôme Loyet has expressed interested in trying to convert the configuration file to nginx style - something Andrei had told me he had wanted to do. The XML throws some people off, thinking it's an actual XML parsed document with XML include support and such... also if done right, this will allow PHP-FPM's configuration to support includes, and who knows, maybe variables some day. But for now it would be a lot cleaner to read, and it seems the majority of PHP-FPM users are nginx users already anyway
I just posted some quick steps on how to get started messing around with the new PHP-FPM.
First, go signup to join the project at the Launchpad Project Page!
Remember this is not production ready quite yet. But download the code, test it out, and contribute. The steps are on the main page to get you started. It would be great if we could get it fixed up so it will work against 5.2.10 or 5.3.0 (and is smart enough to use the same ./configure script to determine it)
We can use many types of contributions, namely:
After a few weeks of people running it in production without any issues, I'm proud to say that PHP-FPM for PHP 5.3.0 can now drop it's "Release Candidate" title and is now in "production"
Download PHP-FPM: http://php-fpm.org/Download
Remember, PHP 5.3.x has a lot of differences than PHP 5.2.x - be sure to read the Changelog, migration guide, etc. located here: http://php.net/releases/5_3_0.php - watch out for a lot of E_DEPRECATED messages
However, I am excited about the performance improvements, mysqlnd, php.ini syntax stuff, support for htscanner like .htaccess file override capabilities and more.
In the future, PHP-FPM will no longer be a patch (at least, it shouldn't be) - there is now a new project on Launchpad that Andrei helped start that is a standalone PHP-FPM. It still requires PHP sources to compile it (for now) but it will allow the project to move at a quicker pace and not be bundled directly into PHP. Join the project and see how you can contribute today! https://launchpad.net/php-fpm/