Two takeaways - (1) The article is bumf wrt the Wordpress.com setup. NGINX plays a role, but the thousands of servers for http, db, memcache, load balancing etc is integral to this discussion (and not mentioned). A typical reader couldn't relate if it did. (2) Directed at a more typical reader, use NGINX for hosting your WP.org blogs, company sites etc. Properly configured, your performance to cost ratio will be terrific. Lastly, on a personal note, it pains me when caching plugins are mentioned as the main part of the solution. No need for these folks. Use the NGINX cache instead and never worry again about a buggy/outdated cache plugin (looking at you W3TC) again. Remove that dependency and you will be happier and possibly better looking.