I added a wiki page to try and gather various discussions and ideas. I linked it off the GRASS 6.3 Feature plan page, in the wish section.
http://grass.gdf-hannover.de/wiki/Extension_development
Maybe it's more appropriate for the GRASS 7 ideas?
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William Kyngesburye <kyngchaos*at*kyngchaos*dot*com>
http://www.kyngchaos.com/
Earth: "Mostly harmless"
- revised entry in the HitchHiker's Guide to the Galaxy