As you can read in this page, facebook boxes are going away. Here's the question and answer from the faq.
No. At this time you can no longer add additional Boxes to your profile. Any Boxes that you have previously added will remain for now, but in our ongoing efforts to improve the user experience and promote consistency across the site, profile Boxes from applications will soon no longer be supported.
Facebook also has a notice for pages. Here's the text of the notice for page administrators.
Starting August 23, we'll be simplifying your Page to make it easier to browse: 1) Boxes are going away, including the Boxes tab; and 2) All custom tabs will be narrowed to 520 pixels. If you have a custom tab, we recommend you visit your tab now for a preview of how your content fits in the new layout -- please make adjustments as needed. The rest of Facebook will see the old tab width until August 23. Read More
Surely, this is old news as it was apparently announced back in October. However, since we are just a week away from August 23, I thought a gentle reminder would be useful.