It seems to me that there are a few plugins for Moveable Type that act as somewhat cornerstones to the whole venture, and that without them, Moveable Type just wouldn't be what it is. That being the case, my thought is, why doesn't Six Apart seek to formally comission a few of these plugins for formal inclusion in the MT system. Or at least as a formal extra or add-in to the system. In that way, further development is encouraged, a certain level of support (for paid licenses) is granted, and so on. As I'm writing this, I'm thinking of two particular plugins, but I'm sure people will think of several more to add in.

For my particular blog, it would not be the same without:

-Feeds.App
-MTAmazon
-Media Manager

What do others think?