MREDRUP  No support, no way to contact the developer, bad all the way around.. I wouldnt suggest this software to anyone and DEEPLY regret my purchase. Oh and did I mention NO SUPPORT?  
(Version 2.0.6)

MREDRUP  Running 2.0.5 on PPC it keeps telling me to upgrade and the FAQ says the upgrade is for all users however it only downloads an INTEL binary over and over.. Please update the notes to say you have dropped support for your PPC customers. thank you.  
(Version 2.0.6)

MACLOVER1.1  One MAJOR drawback is the tiny checkbox, make it very hard to quickly make changes to a filtered list.. for instance I have many duplicates with an added " 1" at the end of the filename and Dupin does not have a way to sift through my filenames and for example tell it to always reject a track if it has a " 1" at its end. SO ANYWAY I need to manually check the one I wanna keep and uncheck the one I want to keep.. which is when that tiny tiny checkbox is really a silly badly thought annoyance as it it hard to clic, responds badly to my nonetheless precise to my Wacom pen.  
(Version 1.4.2)

SLOB  I registered this partly as a gesture of appreciation for Doug's iTunes scripts - always useful - and partly of course to dupe more powerfully than iTunes allows.

So far it's better but not by enough. Specifically I'd like some kind of fuzzy logic for, say, the time length of songs because otherwise identical dupes often show a second or three difference from each other. I wouldn't mind that for names too, eg. ignoring brackets with contents.

Whatever, much appreciate Doug's scripts and look forward to Dupin's further development.  
(Version 1.1.1)

DOUG ADAMS  Note to Leopard early-adopters: a Leopard-compatible version of Dupin will be available following a few days of beta-testing in the wild. I expect a release early in the week of October 29, 2007.  
(Version 1.0.3)