Regarding the benchmark, it is a bit outdated and the apache+mod_wsgi analysys/configuration is totally wrong (i am one of the uWSGI authors, but mod_wsgi is great, and seeing it blasted wrongly in that url is a bit disappointing)
By the way, do not choose your application server looking only at performance.really.
I've followed uWSGI development on and off for a little while, but I never knew about Emperor. I've been looking for something similar for a while. Thanks a lot for your work!
For a good comparison on different WSGI servers (aka uwsgi vs gunicorn, etc):
http://nichol.as/benchmark-of-python-web-servers