@Curt: You wrote: "BRU was extensively updated in the following 3 years, and is now considered bug-free".
It's true BRU is an outstanding product; however, there are a number of serious bugs that remain, especially regarding filenames that contain diacritics or non-English characters. For instance, Regex backreferences within BRU completely ignore any such characters, potentially resulting in seriously maligned filenames (see a more detailed description of this bug here: http://www.bulkrenameutil...wtopic.php?f=4&t=1528).
Thus, although it may be a solid product for English-only filenames, users with a wider character set should be wary. Note also that although the reporting of bugs continues on the BRU forum, as far as I can tell there is unfortunately not much development going on there anymore.