It all depends on the production date your dealer gives you. As a general rule, you can expect the car to arrive about 8 weeks after your production date.
In reality, it appears that production is running ahead of schedule. I had a November build slot for my 997 and I wasn't expecting to take delivery until sometime in January. As it turns out, the car was built around 11/23 and the ship supposedly docked in Baltimore over the weekend. Now unless the car takes forever to disembark and travel the 150 miles to my dealer in Princeton, NJ...I should expect the car to be in my garage by Christmas.