That's exactly the point I was trying to raise--without an integrated framework (like JRE), it's hard to consider Mono and .NET as a cross-platform toolkit. In

That's exactly the point I was trying to raise--without an integrated framework (like JRE), it's hard to consider Mono and .NET as a cross-platform toolkit. In fact, .NET and Mono have entirely different APIs to do UI, while Java is more/less integrated with respect to different JREs (including OpenJDK, Oracle, IBM, etc). People have tried really hard to bring C# on to other platforms even when it starts feeling forced.