The answer is: Yes, for the most part. If you really want to, you can eat the gingerbread pieces, the marzipan (with food coloring, mind you), the royal icing (with food coloring too), the sugar paste, the pretzels, the candies (e.g. jelly beans), and so on. I wouldn't recommend eating the Christmas lights, the battery pack, and the wires though. ;)
Frankly, the gingerbread houses we built weren't really meant for eating. They are works of art! When they are dry, the gingerbread houses are rock hard and can be preserved in an airtight container (or encased in perspex) for years.
Here is a recap:
Our First Gingerbread House: based on The Nightmare before Christmas
This gingerbread house won first prize at the CMHC 7th Annual Gingerbread House Competition on 21 November 2008 (the day we had our Le Cordon Bleu graduation ceremony).
Halloween Town (photo courtesy of the project leader)
Christmas Town
Our Second Gingerbread House: based on Shrek the Halls
This gingerbread house was delivered to the Canadian Prime Minister Stephen Harper's residence on 4 December 2008 (the day the Governor General agreed to suspend parliament).

The outside of the gingerbread house (photo courtesy of the project leader; photo taken at Salle Cointreau, at Le Cordon Bleu Ottawa)

The inside of the gingerbread house
Our Third Gingerbread House: Wilbrod Tree House
This gingerbread house was featured on a local radio program All in a Day (CBC 91.5FM, 12 December 2008) when they were doing a live broadcast at Carlingwood Mall. It is now back in Wilbrod House.

Front view of the tree house

Side view of the tree house. Note that you can see what is inside the house from this side of the house. (both photos courtesy of the project leader and designer of the gingerbread tree house)
So, to the person who bid on and won our first gingerbread house, to the Canadian Prime Minister's family (who have the second gingerbread house), to all who live (and will live) in Wilbrod House (where the third gingerbread house will stay), please, please preserve our works of art!!! Thank you!