I was pretty certain that the answer to this question was "yes" but I needed to check. I've tried my keyboard (wired) with a Dell XP SP2 system in our office and it does indeed work as expected, assuming that you don't expect the media keys to work (they'd need a driver that Apple has yet to release). Keys function as expected on a normal Windows keyboard with the Command key being recognised as the Windows key. The only issue that I came across is that some keys don't do what is shown on them under the default settings, such as the ~ key in the bottom-left of the Apple keyboard - this produced a \ character in Windows and the = key on the numeric keypad doesn't appear to do anything (the other keys on the numeric keypad worked fine). The F-keys/media keys along the top row work as F-keys without the need to hold down the Fn key.
In the end this functionality was more or less expected otherwise new iMac owners would have needed to buy a new keyboard to use with Boot Camp. It is possible that Apple might update Boot Camp in the future with Windows drivers for the keyboard but I don't believe there have been updates to the Boot Camp software since these keyboards were released.
I hope that answers your question for you.