At Digital Photography Now
we use PhotoPost Pro integrated with vBulletin.
In what we feared might be a controversial move - luckily it has not proved to be - we decided to not enable commenting. We encourage our visitors to use the gallery as a staging post for showing their images in the main forum, where we have dedicated boards for comments.
We've had a few teething problems - zip uploads still don't work, for example and we're stumped on that one. Just discovered that quick rating doesn't seem to work (well at least not for admins!). (Actually managed to fix these issues today!)
But otherwise were'e quite pleased and the gallery is gradually being adopted by more forum users.
Digital Photography Now http://dpnow.com