For those who can't wait for the official release of 1.4: I've updated the Volatility Full Dev Installation Wiki to include installation on Linux.
In case you want to automate installation you can use the new get_plugins script. I've only tested it on Mac OSX and Ubuntu, but it should still install dependencies and Volatility 1.4 on other Linux distributions (provided that you have your supporting libraries like libpcre installed already). Feel free to look at the code before running however :-)
Caveat: There is still an issue with the Distorm3 library on Mac OSX and you'll have to compile and install that one manually.