It is a multi-format extractor but the key part is that it has support for RARv3 format and is a replacement for the non-free unrar (in RPM Fusion). unar and lsar are just command line tools but file-roller does support it since 3.6. Once unar gets built, I intend to push the packages changes in file-roller (BR on json-glib-devel and requires on unar) for Rawhide and Fedora 19. I have already tested it with a variety of RAR files and it works fine.
If anyone has any objections, let me know. Thanks