Yes, there is an option in the Bootcamp panel which loads as a service (icon by the clock in windows) that allows you to select which operating system is the default. There is also probably a similar option when in Mac OS X but I have not used it.One question about Bootcamp: can I set my Windows installation be my primary OS so that it loads that automatically without holding alt at startup?
I have mine set to boot into OS X but the choice is there if required.