Well, I notice some progress in the 300 code branch: now 'services_exclude' are handled properly on "More.." command, but 'services_custom' are still totally ignored in all places.
From other hand, there is regression (comparing to 250 code) in other place: when I directly press white-on-orange sharing cross button, I still get all excluded services too.
Please, see following thread for more info (answers are closed, so I can't report the progress there):
http://support.addthis.com/customer/portal/questions/110151-new-addthis-code-js-3-drops-away-all-customized-and-excluded-services-when-pressing-more