We are providing for intermixing of native dialogs and widgets, but we aren't trying to trying to be the Alpha and Omega of UI toolkits. In particular, we currently have no plans to do widgets that aren't universally needed (like Date/Time pickers). We aren't trying to provide for writing the most Mac-like Windows-like or Linux-like (whatever that means) applications; for that you'll probably always have to go native. The platforms we are committed to shipping on are Linux, MacPPC and Win32; but we have an internal need for Solaris in order to do Purify builds.