Be careful with Social Bookmarks Submitter ( *scammers?*submitbookmark.com ), apparently it is from the same person/company as Social Bookmarks Demon ( *scammers?*socialbookmarks.biz ). (NOT to be confused with Bookmarking Demon.)
Some people at WF got scammed last year :
I would stick to SEnuke, and Bookmarking Demon.
Maybe, just maybe, Bookmarking *****. But they also go through Plimus (payment processor) which doesn't get a good word either in the same thread.

Robert