In reply to Jeremy.

Upon giving this some more thought and at the risk of derailing the current conversation even though it's related, I think another solution to this problem is reverting WordPress so that local avatars are supported by core while Gravatar support becomes plugin territory. I'm a bit uncomfortable that between Jetpack and Gravatar, the vast majority of users especially new ones will likely need to register an account with WordPress.com. It's even more of an issue with Gravatar since it's built into core.

I think that the less WordPress the open source software project has to rely on WordPress.com, the better off its users will be. Going back to local avatar storage and display removes at least one of the almost forceful connections to WordPress.com.