I just saw a comment of suggesting J#, and it made me wonder... is there a real, beneficial use of J# over Java? So, my feeling is that the only reason you would even consider using J# is that management has decreed that the company should jump on the Java bandwagon... and the .NET bandwagon. If you use J#, you are effectively losing the biggest benefit of picking Java... rich cross platform support. Sure there is Mono, but it's not as richly supported or as full featured right? I remember hearing Forms are not fully (perhaps at all) supported.
I'm not trying to bash .NET here, I'm just saying, if you are going to go the Microsoft route, why not just use C#? If you are going to go the Java route, why would J# enter the picture?
I'm hoping to find some real world cases here, so please especially respond if you've ACTUALLY used J# in a REAL project, and why.