I use Bootcamp on a MacBook Pro to run Windows7. I also mostly use an external screen and keyboard, and keep the laptop lid closed during normal operation.
When Win7 demands to reboot following an update or software installation, I have to frantically open up the laptop in order to hit the 'option' key to trigger Bootcamp before the time limit expires.
The sensible thing would be for Bootcamp to boot into the most recently used OS by default, but I haven't been able to find a way to configure this.
Is it possible? Any idea how ?