I havn't yet committed, but will soon. Anyway, it is a litle unstable right now, not quite sure why (crashes when selecting different meshes several times).
Anyway, this is part of the DotScene Plugin... Which, I should rename as Plugin_Scene or Plugin_DefaultScene or something.. As, it handles .Scene, .Mesh, .Txt, and OgreProejct (.vop)... So, it is not really DotScene specific.. In fact, I will probably add the Collada and Ofusion scene formats to the same plugin. I contemplated putting the MeshViewier editor into a seperate plugin, but, I will probably instead, just add the basic SceneViewer into this plugin to combine the current plugins.
However, scene editing and material editing can of course reside in their own plugins, as they may grow to be pretty large and use several files/classes/menus/etc. As, the way it is in the other plugins, basically just one class for each file type (and maybe a context menu class). Pretty simple.
Anyway, the MeshViewer will not allow for editing, besides adding/removing lights from the scene, or changing the meshes material. As, there is nothing really to save in terms of a .mesh file type (this editor will not be doing vertex editing or anything like that). The meshviewer may have a export to .xml (via an external OgreXMLConverter app), but not sure of any real use for that. Or, perhaps, it will allow for importing an Xml mesh to a .Mesh (via the converter).. Not sure yet.