Everytime you update your kernel you're going to have to run my wi-fi guide. You need to just follow the directions as listed. Here are some hints and some special precautions.
1. You're really gonna have to hunt to remove ndiswrapper from your system. Run Find and search your drive for all instances of ndiswrapper. They're not hard to find, but there are about 6 instances.
2. Follow the guide.
3. You do not need to redownload the wi-fi driver from Dell, you can refuse the one from the original install.
4. Reboot when you told too.
5. After rebooting you have to turn on your wi-fi card it the blue Fn key and F2 at the same time. (The wi-fi light won't come on when you hit, so don't sweat it) THEN REBOOT AGAIN.