Nice article. I think pound and varnish are not required. Nginx has built-in support for SPDY.

Also, on fresh VPS, whole thing can be automated in 3 commands using EasyEngine - http://github.com/rtCamp/easyengine

1. install easyengine

wget -qO ee rt.cx/ee && sudo bash ee

2. install nginx, php, mysql, postfix, etc

ee stack install

3. setup wordpress at example.com with nginx fastcgi_cache

ee site create example.com --wpfc