This has gotten me written all over it. I grew up 30 miles from MB and have been there more times than I care to count and I have spent several vacations in PF.
Both are tourist traps, but they are other things to do.
If you like the beach, plenty of places to eat and play golf, and some night life, MB is for you. Many, many miles of all of that. Lots of people, cars, but lots of scantly-clad chicks to look at
. Really no where to get away from the bustle except in the middle of a good golf course or on the extremes ends of the strand. Huntington Beach and MB State park are a little quieter, as are some of the northern areas. Lots of shopping and seafood.
If you like the mountains, cool scenery, and Dollywood, PF is for you. We've taken our kids to Dollywood and to Splash Country a few times and it's perfect for our family. The ride through the mountains on 441 is cool. The trip back to Cherokee gives quite a few places to camp, hike, and explore. My kids aren't old enough for that yet. PF has plenty of places to eat and they have a lot of touristy-type places in the 5 miles major drag. You can also shop. You can also go to Gatlinburg, which is another tourist trap with a small drag of places to spend your money.
Comparison-wise: MB goes on and on and on while PF is a small 5-6 mile stretch. For MB, you can start at Pawleys Island in the south and go to nearly Little River in the north and it'll give you around 40+ miles of stuff to see and do. PF is about 7-8 miles from the southern city limits to Sevierville. Google both and look around.
Being a young buck with a GF, I'd choose MB. Thanksgiving in PF will be past the autumn leave changing prime and it'll be cold and a lot more drab than the summer months. I can't imagine anything to do that time of the year up there other than hike or camp. Dollywood is still open, but riding a coaster in cold weather doesn't sound appealing. MB in Nov can still produce pleasant, warm days and the crowds will be thinned from the summer bustle. Good deals can be had.