I’ll likely never start up Windows again, but I’d like to have it available just in case my need becomes great in this Windoze world. Re-partitioning later could destroy your Mac OS X installation and all your precious data that you have on. Better to get it out of the way right away.

I do a similar thing if setting up a non-Mac desktop or laptop, but there I install Linux Ubuntu, and Windows.

I like to imagine Apple adding to the end of their beautiful Mac setup guide a suggestion to delay playing with your new tool and to install Windows right away. Now that would be awkward.

Or I imagine being able to order from Apple with Windows pre-installed. Makes me laugh, partially because it makes too much sense.