You know, when I visited the homepage of Pimp And Host, I fell in love. I knew it was an image hosting service, but the logo for this place is the Mona Lisa wearing a thick chain and gangster's hat - pretty much my ideal type of place to get business done.
So PimpAndHost.com is an adult-focused image hosting service that also has a few extras such as editing and album creation. It's completely free to use and supports GIF, JPG, PNG and BMP file formats. Oh, it'll also allow files up to the size of 5 MB - pretty damn good if you ask me, especially considering that it's provided to you completely free of charge.
Pimp And Host does have a quick upload feature, but I suggest you create an account in order to get access to all of the bells and whistles. It only takes a few minutes and the benefits far outweigh the minimal time required in order to complete the process. So yeah, if you want a long-term solution for the sharing of porn images, this is one potential avenue!