I find it a bit confusing to rummage the forums for extensions wondering if I have the latest code, or someone has added a fix in a post, or was it forked to fit their own needs in another post.
I think a large repository of extensions would be a big selling point for a product such as Sencha.
A central location with an official link on the ExtJS website would be very helpful to developers as well as the community in general. One of the reasons I decided to use a CMS such as Joomla was the list of extensions that were available in a central location that always provided user ratings, history and a single download location, not 30 posts down in a snippet on a forum.
I think it would also be helpful to developers that wanted to offer their code for a price. YES, I would pay for a well developed/well maintained add-on that is supported with every version of ExtJS.
Many developers off their source openly, others want a price. If I like the plugin, I will purchase it.
Please consider a central location for ALL extensions so new users as well as existing developers can find the latest version of extensions/plugins.
To be honest, I am a bit confused as to why Sencha does not see this as a major advantage and selling point for your product.