Oplot++

Just a couple suggestions. First, if at all possible, coordinate your 
work with the KNewPlot folks. It would be nice if your graphing 
package could also be directly invoked from Octave in such a way that 
it would be transparent
to programs ported from MatLab. This would help the "poor starving" 
graduate students of the world to more easily use it.
http://knewplot.paisley.ac.uk/index.htm

Second, try hard to write it such that it will work with Linux, 
MacOSX and Windows. Many of us are limited in our choice of machines 
to just one of the set. (flame wars aside, they all work, but some 
colleges have other ideas on that concept.  :-)     )

I saw a mention of QT at one of the development sites you referenced 
in your emails. QT would be one way you could achieve graphics 
portability to multiple OS's. I am unclear whether it supports Python 
or the other languages/frameworks you were considering. However, it 
is free for non commercial projects.

Your overall goal and example sites looked great. Thank you for 
considering input from others. I realize that your main goal has to 
be to accomplish your own needs. Good luck.

Thanks,
David Gibson