Sharing the moment could be cool I suppose, but...meh, unless we're getting something interesting like a trophy room and achievements that unlock useable/decorative items for the room/OS/menus/whatever they might as well not bother as far as I'm concerned. And if Nintendo absolutely have to implement a boring system then it should be like Steam's system.
I also want achievements that are in fact achievements, not "achievements" that treats me like a retard by rewarding me with medals for finishing Chapter 1. Achievements shouldn't be easy to achieve, that's why they're achievements, that's the damn point! T_T