We upgraded our Gallery today so I will talk.
http://www.bluelight.nu/gallery/
We went from 4.10+ to 4.51. We are happy but have some unresolved problems from previous version that were not solved by the upgrade. I am filling out a support ticket. I suspect this is some personal problem for us.
Even if not perfect, I suggest you upgrade because they are done with the 4.1 level and now every focus is on the 4.5+ level. We waited through beta's and RC's but went for the 4.51. I am happy to answer if someone has specific questions. We run a vb 2.30 with maybe 25 hacks added.
To lurkers: PhotoPost is a software that is an add-on to message board. Your posters can upload images and they appear in thumbnails. People can reply with comments. The database is shared so no one needs to re-register and each picture/comment counts as a normal post.
You can appoint people to be moderators to approve/review the uploaded pictures and monitor the comments, so daily operations are simple for the administrators. If you can believe it, less than a year ago we had an admin devoted full time to manually maintaining a photo page. LOL
I give it a 7.5/10 so not perfection but worth the investment, IMO. Watch for sales or specials to get good price.