Looking in my /usr/local/lib/python.../dist-package directory, I have .egg directories and .egg files. 
Why does the installer choose to extra packages to the .egg directory, yet leave other files with .egg extensions?
I can't explain why some eggs are zipped (the files) and some are directories, but I can offer this: if you hate zipped eggs (like I do) put this in the [easy_install] section of your ~/.pydistutils.cfg:

zip_ok = false
Why does easy_install extract some python eggs and not others?