It is worth noting that the quartet of "
Civil Society, Private Sector, Technical Community including academics, Governments" doesn't map exactly to the multistakeholder groups in ICANN.
In particular the "Private Sector" includes ICANN stakeholder communities that are very divergent in their views, positions and "stakes," and thus need to be viewed separately. These would include the Registries Stakeholder Group, the Registrar Stakeholder Group, the Internet Service Provider and Connectivity Provider Constituency, the Business Users Constituency and the Intellectual Property Constituency (with the latter 3 Constituencies comprising the Commercial Stakeholder Group), as well as many of the ccTLDs (if not the ccNSO as such). These should viewed as discrete stakeholder groups, not as a monolithic "Private Sector".
A number of these groups also map to the "Technical Community" -- Registries, Registrars, ISPs/Connectivity Providers and ccTLDs. It doesn't make a great deal of sense to decide if these are Private Sector or Technical Community. Other ICANN groups that are in the technical community (but not really in the Private Sector) include the ASO, SSAC and the RSSAC.
At ICANN, the "academics" don't seem to show up in the technical community (by and large). Rather they seem to be predominantly involved in Civil Society, which at ICANN seem to be the Noncommercial Stakeholder Group (which includes the Noncommercial Users Constituency, the Non-Profit Operational Concerns Constituency and some members that are not in a constituency) and ALAC.
Governments seem to be the only group that has a similar identity in ICANN as it does elsewhere (although Intergovernmental Organizations don't seem to appear at ICANN; it is limited to direct government participation).
Finally, within ICANN I do not believe that these groups are limited to functioning their "respective roles" as that term is used in the Tunis Agenda.
Greg Shatan