Arjun Mukherjee posits in Future of Computing that J2EE could be the killer app for the CLR. The argument is that J2EE is an excellent architecture but would benefit from the runtime capabilities of the CLR.

While I agree that the strongest aspect of the .NET marketing and technology campaign is the CLR, it is not clear to me what the J2EE spec would look like when deployed on the CLR. It is probably time to head over to IKVM.NET and start reading up.