Facebook Built Some Sort of PHP Compiler
It's not official. There's been no announcement yet, but the PHP community is buzzing about a new compiler written by Facebook.
Alex Handy over at SD Times blogged about this last week. The story is a bit murky, but apparently Facebook has rewritten the PHP compiler to speed up Web page load time.
But Facebook isn't going to keep the compiler to themselves, they're expected to push the code back into the PHP repository.