buffer-local faces?

[David Reitter]

I just found a discussion back in 2002:

Stefan Monnier> I know that I've never understood the point of having  
frame-local face definitions, whereas the need for buffer-local face  
definitions has shown up every once in a while.
Miles Bader> BTW, I want to say I think replacing frame-specific faces  
with buffer-specific faces would be a fantastic idea.
http://osdir.com/ml/emacs.devel/2002-07/msg00198.html
http://osdir.com/ml/emacs.devel/2002-07/msg00254.html

I've been working on a minor mode for a few years now that applies  
"default styles" to frames depending on the major mode of the buffer  
displayed in their (first) window.  That way, users can use a variable- 
width font for, say, latex-mode, but a fixed-width one otherwise.   
Different background colors help distinguish the different buffers  
visually when lots of frames are open.  That said, this is a huge hack  
and causes pain when switching buffers in a frame (frames resize, for  
instance), and the correct way to do these things would be to use  
buffer-local faces.

Has there been any progress with that since 2002?  Is anyone else  
interested in it?  [I don't mean to question a "long-settled issue"  
here, honestly!]