The leading brand by country in 2011 didn't show much change around the world (excluding Europe). Toyota is the big one, closely followed by GM. VW's aspirations at being the biggest in the world is hampered by its lack of strength in so many markets outside of Europe and China.
The number shown after the car brand is the amount of top spots they got. A number after country is what ranking they had for the previous year. No number after a country shows they were top in 2010 also, which is virtually all of them:
BMW - Singapore (3)
Dacia - Morocco
Fiat - Brazil
Kia - Lebanon
Perodua - Malaysia
Renault - Algeria
This list is obviously missing many nations. Any others that a reader may know of, please leave a comment (no registration required) or email me (firstname.lastname@example.org). Thank you.