I've been working in C# for the last five years or so, and I couldn't ever consider going back to Java again, every time I look at some code, even my own, I just see all the nice things that are missing.
There is so much that might seem like syntactic sugar at first, but when you get into it, you can just express yourself in a lot less code compared to Java. Sadly, there also seems to be a culture thing around Java to make things needlessly complicated, whereas the culture for C# is about writing less.
I've started using Jython along with Java at work to get some of the syntactic niceties described for C#. But it would be nice to get the syntax without having to cross language boundaries.
There is so much that might seem like syntactic sugar at first, but when you get into it, you can just express yourself in a lot less code compared to Java. Sadly, there also seems to be a culture thing around Java to make things needlessly complicated, whereas the culture for C# is about writing less.