It seems it is now possible to share photos with MMS to Twitter. It's interesting to notice that the people at Orange UK figured out that if let people send MMS messages to an interesting service you can make a lot of money.
I have never send an MMS in my life and I probably never will, but if the use is interesting or valuable enough, I just might.
The other important thing to notice is that Orange UK can (and probably will) save half of the money (and bandwidth) that would normally be needed to send a MMS. They only have to receive the MMS from their customer. To get the photo to Twitter they only need a few servers that call the API.