I specifically made these builds because Aquamacs annoyed me. Think of them as sort of the anti-Aquamacs. Aquamacs tries to force Emacs into being a well behaved Mac application where, for instance, every buffer is a separate window (which is really annoying when you have multiple hundreds of buffers open). I'm sure there are Mac people out there that will love this and think that it is cool and maybe even The Right Thing. I wanted an Emacs for Emacs people that happened live on OS X and not an Emacs for Mac people.
The Carbon Emacs Package you linked to is more of a batteries included type of distro that aims to add a bunch of extra packages to the stock emacs. I haven't used it lately but it's worth noting that the recently released Emacs 23.1 doesn't have a Carbon port in the main source repo any more. It got replaced with the Cocoa/GnuStep port.