Issue 5 of the X Resource (the published proceedings of the 7th Annual X
Technical Conference) has an paper by Mark Linton and Chuck Price
titled "Building Distributed interfaces with Fresco".

The summary describes Fresco (formerly known as XC++) as an X consortium effort.
Without doing a complete review of the paper, I'll just mention the goals
as stated in one section of the article.  the effort has the goal of providing
the next generation toolkit with functionality beyond the Xt toolkit or Xlib.
Features they want in FRESCO include:

lightweight Objects, such as Interviews Glyphs
Structured Graphics
Resolution independence
Natural C++ programming interface
edit-in-place embedding
distributed user interface components
Multithreading

This by no means captures the complete content of the paper. The Conclusions
sections mentions that a rough draft specification should be available in
early 93, with no schedule (paper presented in Jan 93) for a complete sample
implementation.

I am not affiliated with any of the people or places mentioned above.

-- 
Brian Dealy                |301-572-8267| It not knowing where it's at  
dealy@kong.gsfc.nasa.gov   |            | that's important,it's knowing
!uunet!dftsrv!kong!dealy   |            | where it's not at...  B.Dylan