After worrying that the project had stalled, The Unarchiver 2.2 was released in November and its just as wildly convenient as ever. I really like the phrase "wildly convenient", not sure where I picked it up but it works on so many levels.
The Unarchiver is a beautifully written little application that replaces the functionality of the standard Archive Utility in OS X and lets you uncompress virtually* any archive you'll encounter right from the Finder. Even from an Amiga!!!
Given I mostly live inside the Terminal with Midnight Commander for most file management tasks my need for a graphical front end to a dizzying array of compression algorithms is perhaps less than it once was, but it's still a fantastic tool to have just in case, and I wholeheartedly recommend it to all my Mac friends who are terrified of the command line. Well that was a long sentence.
As for the asterisk next to the word virtually above, the only compression algorithm it still doesn't resolve is rzip which is a bummer because it's my primary one. It's FLOSS software, so maybe I should submit a request and a patch.