I also like the Rottweiler breed.
I've had them for the last 15 years, and don't plan on switching.
Also, someone mentioned earlier about the Rottie being "big and dumb"(mentioned in a nice way), but Rotties are one of the most intelligent dogs. It's just that they are very stubborn and hardheaded, and have their own ideas about what they want to do.
Here is the list of top 10 most intelligent dogs, that I just got from a web search.
Rank Breed
1 Border Collie
2 Poodle
3 German Shepherd
4 Golden Retriever
5 Doberman Pinscher
6 Shetland Sheepdog
7 Labrador Retriever
8 Papillon
9 Rottweiler
10 Australian Cattle Dog