From Fedora Project Wiki
%autosetup as a replacement for %setup that handles patches directly without having to manually list them one by one was introduced in 4.11 version of RPM (Fedora 19) and there is no reason not to recommend it over %setup everywhere except for EPEL
http://www.rpm.org/wiki/PackagerDocs/Autosetup
https://fedoraproject.org/wiki/Packaging:Guidelines has a few examples where %setup is used. This should be replaced with %autosetup with a note that EPEL package maintainers (before EL7) should continue using %setup or wrap it in %ifdef macros.
PS: Considering https://fedoraproject.org/wiki/Make_install_packaging_draft was approved Please use it in the examples provided in packaging guidelines as well.