There is also this list: http://wiki.blender.org/index.php/Extensions:2.6/Py/Scripts
I wrote the structure for the Wiki scripts catalog for Blender 2.49, then we ported to Blender 2.6.
It needs a rewrite, which I will do hopefully in the near future.
The idea behind the wiki catalog was to provide a single place for script writers to show there tools.
The wiki is the best place to describe & document your addon. The links don’t disappear after a year or two is one benefit.
My addons_extern catalog is a collection of addons old & new that still work. many I fix myself & often I use this as a platform to test addons & develop before adding to Blender. It is also the home of many ‘unmaintained or orphaned/lost scripts’ & a collection of ‘working scripts all in one place’ just as wiki should be ‘scripts directory’ all in one place.
What’s needed is man power to help. Help in:
Blender Official addons (Release Addons),
Blender Addons Contrib. (Addons developed in the Blender git environment with the goal of being included in Blender),
D/l snapshot of addons contrib here: http://git.blender.org/gitweb/gitweb.cgi/blender-addons-contrib.git/snapshot/HEAD.tar.gz
(Addons Contrib is also included in Blender buildbot builds here: https://builder.blender.org/download/ )
Addons Extern is not official, but a library of addons that get submitted to blender & not allowed, or forgotten about, or orphaned or useful tools & most of my working collection.
There’s help needed on many levels.
The wiki catalog should be the place for information & list of scripts. Much help is needed to improve it, but it’s a popular & very useful site, where links to information & addons can be maintained & have ‘everything in one place’ permanently.
Blender Addons Release needs more help, often Blender developers feel that Addons get written, approved, & the Author disappears & they are left to maintain all the addons. Indeed often I find myself fixing addons for Blender that I don’t use but know their use. Often I find myself bugging authors or dev’s, “Can you fix this?”, “What happened in the API this time?”
Blender Addons Contrib needs some major work. To clean it up & fix/remove addons, there is much help needed.
That said, there is also an awesome community of addons developers who help when they can & write great addons & documentation.
I would ask addons devs to use the system Blender has provided, scattering lists of links across the web, is difficult for users, the one place should be the wiki catelog, let’s improve that for a lasting & comprehensive guide to all that’s addons.