I have installed PyCharm 3.4.1 CE for my Mac. I was able to install the jade plugin from
Preferences > Plugins > Browse repositories
Problems found loading plugins:
Plugin "Jade" was not loaded: required plugin "com.intellij.css" not installed.
Open plugin manager
The Plugin depends on com.intellij.css. It is only part of the Ultimate Edition. There is no support for the plugin in the CE.