I understand, but since the normal workflow for egg creation and uploading
doesn't involve any renaming steps, I'm classifying this as a low-priority
feature request (to verify that an egg has not been renamed, after download but
prior to installation).

I doubt it is the case that *nothing* can be done about it.

For example, off the top of my head, it seems that the version number inside the
egg could be checked against the one derived from the filename.  If they
disagree, a warning could be emitted so the user is aware that something might
be wrong.

Unfortunately, that name means "pyOpenSSL, version 0.9.py2.5-winxp32", which is
a perfectly valid (if weird) version number, of an egg which is not specific to
any particular Python version or platform.  There's really nothing that can be
done about a renaming that results in a valid, but wrong version, any more than
anything could be done about renaming that gave it a valid, but wrong project
name, Python version, or platform.

Due to user error, an egg which should have been a Python 2.5 Windows binary egg
got renamed to "pyOpenSSL-0.9.py2.5-winxp32.egg" and uploaded to PyPI. 
easy_install will select this egg for installation on Linux, though it is not
usable on that platform.