Does Facebook now hate MMS? For the past couple of weeks every time I tried to send a photo I got the following error message:
"You have uploaded from an unrecognized address. For instructions on how to upload photos to Facebook, go to http://www.facebook.com/mobile"
I got this sending to both mobile@facebook.com and 32665. The referenced page is no help at all, and my phone number is registered with Facebook Mobile.
It turns out that there's a new secret email address. On the Facebook site click the icon to share a photo:

Then click
Upload a Photo:

Then click
upload via email:

Your personal email address is finally revealed and can be used to send a photo via MMS.
Facebook - update your error message to point this out!