Picking a gallery for your Community Builder site can be difficult. You need to consider how you will use it and how large your community, and therefore your gallery, will become.
Gallery 2 is a great gallery with many features (too many to list visit the Gallery 2 website ) and we should all be thankful for the great bridge that Michiel Bijland has made. With the Gallery 2 bridge you can have users created in Gallery 2 whenever someone registers in Joomla/CB. You can also configure Gallery 2 to create a new gallery for each user. You can even decide when the gallery is created (when the user account is created or when the user first logs in (very cool!). You can also assign quotas to each user. Quotas should be in every multiuser gallery to control how much disk space your users can use but unfortunately not all galleries have them. Gallery 2 is nearly the perfect solution if it wasn't so resource intensive. If you have a small and not very active site you should have little to no problems. If you a large gallery with a very active site you are in for a world of painfully slow page loads. If you read in the gallery forums you will find that other people are having this problem too if you aren't comfortable taking my word for it. The Gallery guys have said they are going to try to speed things up in future versions but if you need a solution now Gallery 2 may be out for you.
Zoom Media Gallery is made to integrate into Joomla/Mambo. It also has many features like uploading a batch of pictures, lightbox, magnify, comments and on and on (visit zoomfactory.org for a full feature list). This makes it a great gallery for a standard Joomla/Mambo site but it falls for Comunity Builder. It actually has a good plugin and seems to work great with Community Builder but until it has quotas for users I wouldn't really consider this a great component for a CB site. It is hard for me to say that because it works so well with Joomla, has some nice addon modules and doesn't weigh on your webserver like Gallery 2 does. I couldn't find any replies to users asking for quotas in the Zoom Media Gallery forum and it doesn't seem to be on the roadmap. Bummer!
Community Builder Profile Gallery plugin is made specifically for CB and created by Nant, JoomlaJoe and Beat ( all core developers of CB at joomlapolis.com ). It is easy to use and as far as I can tell so far is lightweight so it should be able to handle a large active site with many users and photos. CB Profile Gallery also has quotas as well as the ability to limit how many files a user can upload. So say you give each user 1MB with up to 10 files. That means a user can upload five 2MB files and reach his/her limit or upload ten 250KB and reach his limit. This is a very nice feature and gives the you ,the administrator, the kind of control you should have. CB Profile Gallery looks very promising and may be the solution you need. The downside of CB Profile Gallery is that it doesn't have the ability to upload more the one file at a time and you can't edit the properties of a picture once it is uploaded. You need to delete the picture and then upload it again with a new description. Not terrible but not convenient for a user either. I expect this plugin to address all these issues in time. It is kind of unfair to compare it to Gallery 2 and Zoom Gallery which are so much more mature in terms of time and development. Give CB Profile Gallery a little time though and it should be perfect for use with CB.
Coppermine - There is no plugin yet