RPM 6.1 has fixed a number of LLVM/Clang compilation errors and warnings for those building RPM outside the confines of the GNU toolchain. RPM 6.1 also brings improved keystore locking, restoring the NSS-based user/group lookups by default, support for literal and one-shot macros, new %define options, improved build and verification error handling, and better usability of the rpm-plugin-syslog plug-in in conjunction with systemd's journald. On the documentation side are also new man pages for RPM.
RPM 6.1 introduces a new release model that they say is inspired by the Linux kernel. With RPM 6.x, major versions indicate the RPM package format, minor releases contain new features and bug-fixes without breaking things, and micro releases are security and bug-fixes only. RPM minor releases will happen more frequently but yet to be determined exactly how frequent.
More details on today's RPM 6.1 release can be found at RPM.org .