In fedora is new package man-db with the similar functionality like man. Both packages - man (from man-1.6f-29.fc14) and man-db provides: man-pages-reader, so the requires dependency in this package should be changed from man to man-pages-reader. (Details see thread: http://lists.fedoraproject.org/pipermail/devel/2010-March/132647.html)
Dependency changed to %{_bindir}/man in rpmdevtools 7.8-2. I don't see any benefit of man-pages-reader over %{_bindir}/man -- on the contrary actually: using it would cause an incompatibility with older distro versions.
rpmdevtools-7.10-1.fc13 has been submitted as an update for Fedora 13. https://admin.fedoraproject.org/updates/rpmdevtools-7.10-1.fc13
rpmdevtools-7.10-1.fc13 has been pushed to the Fedora 13 stable repository. If problems still persist, please make note of it in this bug report.