IMHO it's kind of silly to expect things like WPF to run on multiple platforms - and I'm actually glad it does not. The world doesn't need more apps with lowes

IMHO it's kind of silly to expect things like WPF to run on multiple platforms - and I'm actually glad it does not. The world doesn't need more apps with lowest-common-denominator UI. Ugly, kludgy, doesn't work well on any of its platforms because it cannot leverage any platform-specific UI strengths. If anything, the last decade of desktop and mobile computing has shown beyond a doubt that a highly refined user experience is paramount for anything that faces general users. In fact, an app with fewer features, but a superb user experience, will trounce a more capable app with terrible UI (see: Apple). This is also why I dislike apps that use the UI components from Java - they don't look, feel, or work like native UI widgets. Their layout is often confusing, since they are trying to appease the learned design patterns of multiple disparate OSes with a single design. They end up being awkward, frustrating, and a very poor experience. I have never met a Java-UI app that even reached an acceptable level of usability. For me, having Mono run well with the obvious cross-platform bits (threading? file system access? etc etc) is enough. I for one really like C#, and would much rather write it than Java.