Please separate the usernames within ArcGIS Online for Organizations accounts from the global Arcgis.com namespace.
Jonah.Wail working for Humpbacks United is not the same Jonah.Wail at Pacific Tsunami Watch. Within the current global name space structure in order to distinguish these two people we need to resort to awkward conventions like
jonah_wail_humpbacks_united and jwail_ptw and jwail23
The 1st has the benefit of being communicative. People quickly understand which organization that account is a part of. It's horrible for the user though, especially when trying to type on a mobile device. The 2nd is nicer for the user to enter on a regular basis but it sucks for people browsing the galleries or otherwise unfamiliar with the person and/or organization.
Both are easily confused with the Jonah.Wail who's not part of any organization, just a random cetacean exploring arcgis.com and putting up bubble net maps. Nor do they accommodate the Jonah Wail who does work for Humpbacks United, but has his own hobby maps that he makes and shares just for fun.
The 3rd is a problem because jwail32 and jwail23 have very distinct and diametrically opposing viewpoints: save the whales vs eat 'em, we're hungry.
All of these problems are solved or at least greatly lessened by having separate name spaces. Think of email. No one is likely to confuse jwail@eat-whales.com with jwail@save-the-whales.com.