Safari for iOS6 supports the mime type: application.com/vnd.apple.pkpass This means you can download & open Passbook .pkpass files from a URL.
It seems that Facebook's browser does not support this mime type and therefore you can't download Passbook files from within Facebook. Instead you need to 'Open in Safari'. This is a problem because a great way for a business to distribute links to a Passbook promotion (e.g. a coupon, membership, gift card or event ticket) is via a Facebook marketing campaign.
How can I find the right people to contact at Facebook to request that Facebook iOS App browser supports the .pkpass MIME type?
Thanks if you can help, Andrew