I downloaded the openSuse 10.3 / Mono 1.9 VMWare package to test my app with. However, it crashed almost immediately. After a fair bit of debugging, I discovered that OnResize was being called before OnLoad on my GLControl. The code used to work fine on Mono 1.2.6, so I presume this is a change in Mono 1.9.
Anyway, just to bring up the issue. I use OnLoad to Initialize the gl contexts, etc, and Resize to change the viewport and perspective. I figure this is a common design pattern, so if others use the same mechanism, be aware of the change.