One notable absence was README.md... :)
For the testdata/*, I now use `include_package_data=True` in setup.py, to automatically install any data files found inside package directories that are also specified in MANIFEST.in file.
I also include the Snippets, which I think should belong to the source distribution, despite not being installed as console scripts like ttx, etc.
The MANIFEST.in does not need to include itself (done by default).