For what it's worth, I'm in favour of sticking with the current 80 character limit. It's really not hard to work with or accommodate. In my workplace, I go much wider, but we all have standard environments and it's no big deal.
80 characters looks narrow to me, but I can adjust, and it makes sense to use this as a common denominator for a widely-shared piece of code like the Python core libraries. As everyone has said, it works well in emails, funny terminals, vi, emacs, IDEs, can be easily used side-by-side with other open editors, etc. These 'special cases' seem very remote until you are suddenly confronted by them. For me, the most common is when telnetting / sshing into a foreign machine which assumes an 80-character width and the terminal emulation setting is a bit mucked up, so all of a sudden you can't resize to make use of your screen real estate. Trying to read code over such a link, or through a funny email client which wraps long lines, is awful and I'm happy to accommodate those people.
Working with the 80-character limit is really easy in my editor, and it's certainly much easier to fit in with the existing style of a shared codebase than to have idiosyncrasies within sections that have been edited here and there.
I don't think the 80-character limit in PEP-8 is doing many people a great deal of harm.