I use virtualenv heavily and still do the symlinking dance. I keep my django trunk in a ~/libraries folder and symlink the django folder to the /path/to/virtualenv/lib/pythonX.X/site-packages folder. I'm not sure that I have a compelling reason for doing so.
I would suggest to stop doing that since thats the point of virtualenv; it is a bit of pain since it doesn't put django-admin.py in path but you can always refer to it.
I use virtualenv heavily and still do the symlinking dance. I keep my django trunk in a ~/libraries folder and symlink the django folder to the /path/to/virtualenv/lib/pythonX.X/site-packages folder. I'm not sure that I have a compelling reason for doing so.