@renem, @manton has implemented Webmentions, but a filtered version. If I recall, mentions are only sent to the website listed in your account settings and not to others. Although, now that I'm thinking about it, perhaps it could be a selling point for expanding the user base of micro.blog if he let all @mentions and @replies send Webmentions. Barring that it would be nice if there were additional fields for more websites which could receive them as I use two different sites to feed my micro.blog account, and currently only one of them can get these "whitelisted" Webmentions.
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