This is quite minor, but since the urlgrabber package has been renamed python-urlgrabber some time ago, the explicit requirement in yum hasn't been updated. This isn't really a problem, but I did run into a case where it got confusing : On a bare minimal FC5 installation, yum wasn't installed. Downloading it and trying to install it with rpm directly gave some unmet dependencies, of which this one, which would be nice to have indicate the actual missing package name. Quick fix : s/urlgrabber/python-urlgrabber/ in yum.spec Requires :-)
The reason it's kept this way is to try to keep the spec in as close to sync with upstream as possible.