My boys are very, very happy. Last night, they were throwing ideas around as to what we should do for dinner and what activities should follow. As far as Christmas goes, it was the most animated I've seen them since they were little boys.
So happy it worked out well for you! I bet on some level, your parents are relieved. When they start ordering take out for family Christmas, it is a sign that it is beginning to be too much for them. I think it is good to acknowledge to them the strong traditions they have started that you are going to continue, such as Christmas Eve being the "main event". Let them know they started it, you have such fond memories of it, and you plan on keeping those traditions, same day, just a different location, which you hope they will continue to share with you. This way they can be the "guests of honor" and enjoy their daughter and grandchildren without the stress of hosting the event themselves. Just make them feel special and important. Maybe your kids could write little notes, tied to branches on a small table top Christmas tree, of their favorite memories of Christmas (and just in general) at Gram and Grampa's. Maybe they could take that tree home and read the notes to remind them how special they are. Maybe a few hand made ornaments from the kids on it and a homemade treat to take with them as well. They sound like wonderful parents/grandparents. So happy for you and wish you the best in your "first" Christmas at home!!