ySlow speed is complaining about expires headers not being set.
Should gzippo have an option to set this as well as cache-control?
It does currently set the expires header however only to one day. It is a bug and should be defaulted to one week.
It seems that Connect doesn't implement support for the Expires header: senchalabs/connect#410 however gzippo does for gzipped content.
Hm, I do see expires header in current version?