CamelCase vs. all-lowercase package names

[Rhubarb Sin]

PEP-8 calls for "short, all-lowercase names" for packages:

http://www.python.org/dev/peps/pep-0008/#package-and-module-names

On the other hand, The Hitchhiker's Guide to Packaging 1.0, under
"Background," declares "come up with a CamelCase project name":

http://guide.python-distribute.org/creation.html

On PyPi, of course, there is great variation. At this point is there a
more formal recommendation for a package naming convention?