2008/11/3 geni geniice@gmail.com:
Okey lets consider photobucket as an MMC. It allows anyone to register (and then nags you if you don't use the thing but eh). It allows you to take any image download it, edit it and (because they largely ignore copyright issues) re-upload it. And the ability to do all of this is at least as prominent as wikipedia. You therefor accept photobucket as an MMC.
I don't really care about whether PhotoBucket qualifies as an MMC, and I won't investigate their site interfaces to decide that question. IMO Wikimedia wikis, especially with the external editor interface, certainly do.