Redundant operations and wasted time and resources spent duplicating work already done by another of its eight different brands have plagued GM for years. The carmaker has been long criticized for its organizational structure but it has finally confirmed the merger of its eight brands into four distinct channels – each headed by newly appointed vice presidents.

The U.S. marketing and field operations will be more strongly aligned into four retail channels: Chevrolet; Premium (Cadillac, Hummer, Saab); Buick-Pontiac-GMC; and Saturn. GM will also further streamline the organization to reduce complexity and align resources to help improve profitability and regain market share lost to Toyota – one of the world’s most efficient companies.

One of the new execs is former Nissan and Infiniti VP Mark McNabb who has just been appointed as the head of GM’s premium division, which covers the Cadillac, Hummer and Saab brands.

Some of the areas GM is improving is changing its portfolio to highly differentiated vehicles for each brand. For too long each GM brands competed with each other but the first changes are already starting to appear. Buick for example has been geared up for luxury sedan models, while Pontiac will specialize in performance models and GMC is sticking with trucks and SUVs.