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This is great Amanda!
However, I noticed you have to approve all the images, not only Avatars but also images posted in the forum within a message. I don't think that an "approve first" policy works well in a community. I would suggest you to use an approach "check later and remove" or at least enable users who are already "trusted" to publish images. You don't have such a policy in MSDN forums, I don't see the reason to use it here.