.NET or CORBA?

DavidTurner queries: "My company is developing software to integrate various hardware systems and present a unified interface, plus system-level interaction. Essentially, an object hierarchy plus supporting services - clients, servers and drivers. We wish to replace our proprietary protocol with a standardized distributed object system. The choice has boiled down to .NET versus CORBA+GTK. We want interface contracts, OpenGL support, and embeddable forms (widgets). We also want rapid development. Which would you choose? Has anyone actually field-tested the relative merits of the two paths?"