The Sun research is pretty outdated, that was probably around 20 years ago that happened. I don't think any of it is relevant anymore.
There are still ongoing user studies happening in GNOME and KDE. It's probably not anywhere near as rigorous as at Apple, and I doubt you can easily assign a dollar value to it, but it does happen.
There are still ongoing user studies happening in GNOME and KDE. It's probably not anywhere near as rigorous as at Apple, and I doubt you can easily assign a dollar value to it, but it does happen.