I'm using Gnome and switched my theme today. After that, Wuala was nearly unusable since some Buttons and Labels where not visible any more (same color as the background).
As far as I know, wuala is coded mostly in Java which provides basic theming functionality. It would be helpful, if wuala would use this possibility to integrate better into different Desktops (Windows, KDE, Gnome).
But of course it's not *that* important right now ;) So thanks for your great work!