to fix immediately:
Improve printing of diagrams.
(Improve) Compute pKa's of functional groups.
Add more lone pair/orbital symbols.

Longer term:
- Improve interoperability with OpenBabel (perhaps abolishing my custom
  Molecule classes in favor of OBMol)
- Browser plugin (Mozilla for Linux/MacOSX, .NET on Windows)
- Retrosynthesis
- Implement Convert to 3D.
- Link to 3-D visualization programs of some sort
- Improved XML support -- standards like SAX and DOM...

For Qt4
- antialias option
- cmake, qmake or autotools?
- use Qt resource system instead of RingDir?
- find a way to replace Q3PointArray (beziers)
- use more pass by reference (const QString &)
- make use of Qt's Postscript and SVG output capabilities?
- improve previewwidget