They have been discussed at various times in the forums, but it seems to have gone cold recently - I guess with 0710 coming. From what I gleaned from those discussions, though, it sounds like a huge task because of what the orbiters have to be able to do with things like regens and so on. The discussion moved towards a complete re-write, so that all those things like skins you mention, dynamic content, and as importantly (to me!) the cooler graphical effects.... yes we have alpha blended (sometimes!) but really the rest of the interface is completely static, no transitions, fades, wipes, etc, most of which, ironically, are simpler graphically than alpha blending!
I'm just catching up with the UI revision discussion
(re)started last week in the developers maillist. And with the UI3 proposal
started last week in the wiki. There's really so much discussion and development going on in different niche media available to this community that it's ironic how integrated is the final product.
I think the maillist posts should all be automatically posted to a searchable forum, and subscribe the maillist to notifications of posts in that forum. And the mantis wiki link should point to a "bugs/issues" category in the single, unified wiki. And I think LMCE itself should have a link to a single portal page for all that.