No, you must purchase the new iWork applications if you bought them on disc. You have been able to update via Software Update, but upgrades are paid. The software just hasn't been upgraded since 2009.
Turns out it is easy to solve. Try this: http://forums.macrumors.com/showthread.php?t=1657954
I take it back! My apologies . Thanks for the tip on this. It's a shame this method doesn't automagically add the newer versions to one's Purchase History in the App Store, though. Have to install the old ones before you can update .
EDIT: Looks like it does, in fact, add the new iWork apps to one's Purchases. Even better!