Six Apart only seems to have this stale, tiny bit on using text formatting in MovableType 2.6x. I know I've blogged it before, but Timothy Appnel's treatise on writing Movable Type plug-ins has the goods on the innards of text formatting plug-ins. I finally put two and two together and realized that MT entries in XML can now be processed with XML tools, through text formatting plug-ins. Now Movable Type is even more attractive as RSS aggregation infrastructure.