Facebook is now built on HipHop, but not the way you may think. HipHop is a customized version of the PHP programming language of which it is built on. Facebook hired a team of engineers to optimize the language to deliver better performance for itself and a better experience for its users. A win-win in both case; Facebook can deliver its webpage more efficiently and support more users and their users can continue to use the site hopefully without issues.
As a programmer myself, I can appreciate the need for greater performance and scalability (ability to grow) of an application. Nothing turns people away faster than a slow web site (knock on wood) and the feat itself isn’t something to be taken lightly or even something that is common place.
Of course the Hip Hop side of me recognizes what just happened with Facebook’s HipHop. This is a blatant attempt to capitalize on a name and cause brand confusion to help boost exposure. While we appreciate the honor and are flattered by your choice of names, we don’t need your confusion added to our culture. Especially in these times of coping others work and using it as your own.