I'm the proud owner of 4.0.
There are a few issues I've noticed already:
1. The "right indent" for bulleted and numbered lists doesn't work.
2. The browser doesn't show an image of Word files like it (sometimes) used to. A file viewer for common applications in the browser would be a big advance!
3. Full featured hoisting including columns (especially in "Filter" result screen) is needed.
4. A few more key buttons would help on toolbars.
Dr.J