The marketplaces demands drive much of that - the largest percentage of users are vBulletin users, so it is natural they would get most of the attention. For myself, I use two boards: .threads and vBulletin and code for those two boards.
For something like a phpbb photo block, it would require someone who has some knowledge of phpbb and PhotoPost, which I do not have enough of to offer to help. Keep in mind we support over a dozen forums, so being proficent enough to code modifications in each one would be a challange in itself; that's why we rely on community participation for things like that.
Maybe you could offer your mod to other phpbb users?
Please do not PM me for support or sales questions. Thank you for your understanding.