Any AEM setup where a dispatcher is used. NginX outperforms Apache: NginX is faster than Apache, has a smaller codebase and can handle more request than Apache with less load on the machine. It would be beneficial for both the Adobe's server (because NginX is lighter for the machine) and the client (because NginX can handle requests faster).
No NginX support
Environment Details (AEM version/service pack, any other specifics if applicable):