Should You Have Seating Assignments on Thanksgiving? [poll]

This is a really big year for us.  For the first time ever, my wife and I are going to be hosting Thanksgiving with more than just us and our two kids.  Going from the four of us, to a house of fourteen has brought up some questions.

Our guest list to date includes my dad and his "woman friend," my aunt, my wife's parents, her brother, and her sister, who'll be bringing her husband and two kids.  We're currently looking at a house with about 14 people when all the heads are counted.

So far, you've been really helpful with all my Thanksgiving questions.  Last week, you said that it was okay to ask guests to bring a side dish on Thanksgiving.

Now, I have another question.  With so many people, is it better to have seating assignments or just let everyone have at it?  What's worked best for you?