The NYT has a piece discussing efforts by Ford and GM to improve their quality. There is a chart accompanying the article showing the trend in complaints for the three automakers over the last decade. It shows a sharp drop in complaints by model year for both Ford and GM, while the numbers for Toyota remain almost flat.
The picture is somewhat distorted since it doesn't take account of sales. GM and Fords sales both fell by roughly one-third over this period, while Toyota's doubled. This means that Toyota also saw a sharp fall in complaints per vehicle, while the declines on a per vehicle basis for Ford and GM are not as steep as indicated by the graph.