Currently, there are two main Repository's for scripts.
Firstly, For Users:
The catalog contains links to & some documentation to 100's of scripts.
If you are a script writer, or you see your script there,
I would ask that this be your first step in updating your scripts & docs.
The wiki scripts catalog is very popular & many people around the world,
browse & even update their scripts!
Documentation, much of which can be copied from your site to the wiki,
is very important, this does not stop people linking to your site.
Please, if you do not have an account to edit the wiki,
ask on irc #blenderwiki that you need to join,
or send the e-mail request.
It's easy to edit & help is available.
The centralization of Blender Scripts & Plugins helps script authors, Blender,
& general users, use Blender & Python more effectively.
Next, For Script Writers:
Script Authors are encouraged to use this New Repository.
After you have (preferably) written docs on the wiki, containing links & some information. The Script Author can request to or be asked to,
upload the script or plugin to Blender Projects: Blender Extensions.
Py Scripts Upload
For scripts that are in development, (or unmaintained/returning errors).
There are already quite a few scripts here,
these scripts are still useful, but may be still under development,
working, but in need of updating/extending, whilst still useful in bringing ideas & extra functionality to Blender.
Py Scripts Contrib
For Scripts that are stable, fully working & providing extra functionality to Blender.
These scripts should be reasonably documented & well maintained to the current version of Blender.
Scripts in Contrib, must at minimum have:
Some form of docs. Wiki preferred.
Some form of license. GPL , CC, BAL are preferred.
My preference here is GPL, as it offers protection to the script author & is widely used.
The script should provide a function that is not easily acheived in Blender or a New Function or a new easy way to do several functions.....
These scripts will be available as a Branch & be able to be compiled with Blender.
The same will apply to Plugins.
Work is in progress on this & svn checkout should be availible shortly after 2.49 release.
There will be a view towards upgrading/merging many of these scripts for 2.5.
I would ask Blender 2.4 series script writers to upload their scripts soon,
so working versions for 2.49 can be saved, before the change to Python 3.0 & the new API will change back compatability with Python 2.5.2