The same gentleman who helped make it possible to fix the docs upload bug also suggested the start of a fix for the MIMETYPES bug we get with python-gdata versions 2.0.15 and 2.0.16 with the fix (with or without this fix, we can't upload docs via python-gdata 2.0.15 or 2.0.16, so the fix was still worth publishing).
The error I get now is:
AttributeError: 'module' object has no attribute 'DocsEntry'
A quick grep of the whole googlecl tree for the term "DocsEntry" shows me that it only exists in gdata versions 2.0.11 and 2.0.14. . . So why does GoogleCL call for it in the trunk/src/googlecl/docs/client.py file? The call for it seems to work with python-gdata 2.0.12 -- I can upload documents of txt and pdf types without a complaint about DocsEntry.
Edit: Resolved this issue and blogged about it here.