Sorry, don't know where to discuss this...
Alternativeto.net present Pidgin as an alternative to Adium that is usable on Mac OS.
Pidgin and Adium are both multi-protocol aware instant messaging clients. More technically most share some major components, since Adium is mostly a Mac OS specific interface to Pidgin's core libraries.
Pidgin can also be installed on Mac OS, though this use case is not clearly supported. The application has to be compiled manually, and then the application runs in the X Window environment, providing a user experience that is absolutely not on par with that of Pidgin on other platforms, or that of Adium on Mac OS.
Pidgin's team themselves recumbent the use of Adium for Mac OS users. For example, the Pidgin's download page provide no installation package for OS X, rather provide the following claim: "For a native Mac OS X experience we recommend Adium, which uses libpurple (the core of Pidgin) for much of its protocol support." A similar assertion can be found in Pidgin's installation instructions (at https://developer.pidgin.im/wiki/Installing%20Pidgin): "Can I run Pidgin on Mac OS X? Yes you can, but we do not provide a package for it. The reason being that in order to use Pidgin on Mac OS X, you need to install an X server and GTK+, which we are not prepared to support. You can either compile Pidgin (and its dependencies) yourself, or you can use the fink installer available from ?http://fink.sf.net. If you would like a native aqua interface or a user-friendly installer, we suggest trying Adium, available at ?https://adium.im/."
In the end, I don't disagree that Pidgin can indeed be presented as an alternative to Adium on OS X, but the very high number of "votes" associated to Pidgin, due to its popularity on other platform, make it appears as a much preferred alternative to Adium on OS X, though its actual use on OS X is marginal and unsupported.
Now, I am new here as a participant, so I'm not sure how to best resolve this issue. I can think of three approach to this: either remove Pidgin as an alternative to Adium (and other Mac OS instance messaging clients), or remove platform Mac OS on Pidgin, or split the Pidgin application into two distinct applications, let's say Pidgin and Pidgin on Mac, which would more exactly position Pidgin as a possible though very unpopular alternative to Adium (or any other mac instant messaging application for this reason).
So... Comments? Advices? Commons practices?