How are you enabling NURMS? I select the object, right click, and from the menu hit "NURMS Toggle" which is the very first option in Max 2011. I don't know if your problem is exclusive to 2010, but there's a chance enabling NURMS in a different way could fix it :)
I've always used ctrl-m to turn on/off, i believe that's the default shortcut. The problem is not with turning it on or off, but the way it's being displayed in the viewport, strangely enough when i turn on the wireframe i see the subd version appear, selecting the object turns it on again. I found a way to fix it by…