Just found out that the moderation is definitely outsourced to Concentrix and the office is in Costa Rica. Before people said this but I wasn't sure if it was true.
On the Concentrix Costa Rica office's Facebook page there is a photo album called "Habboween 2012" with pictures of the outsourced moderators in Halloween costumes. In some of the pictures, Habbo is visible on the computer screens in the background. There is also a picture showing the office with Habbo signs attached to the roof, marking the office space for the moderation of Habbo.
Images in spoiler:
There are many more pictures in the album on the facebook page.
I know this has been known by quite a lot of people, but It was just rumors really, nothing was proven.
Link to Habboween album of Concentrix's facebook page http://www.facebook.com/media/set/?s...8864153&type=3
Link to Concentrix Costa Rica office facebook page http://www.facebook.com/ConcentrixCostaRica