Every December, the Nasdaq stock exchange revises its list of the 100 biggest nonfinancial companies trading on the market, ushering in companies on their way up and kicking out those who fell behind the curve. This year the exchange is welcoming a dozen new companies into the fold, including game publisher Activision and graphics chipmaker Nvidia.

　　"The re-ranking is a unique event in that investors ultimately determine which companies are members of one of the most closely followed indexes in the world," John L. Jacobs, executive vice president of Nasdaq, said in a statement. "The re-ranking process is objective, rules-based and transparent--one that ensures the Nasdaq 100 Index will continue to be an important benchmark by which you can invest in a diverse array of Nasdaq-listed companies."

　　Activision and Nvidia join respective game-industry rivals Electronic Arts and ATI on the Nasdaq 100, which also features the likes of Dell, Intel, Pixar, and Starbucks. Google, Urban Outfitters, Expedia, and Monster Worldwide were among the incoming Nasdaq 100 companies, while Dollar Tree Stores, Novellus Systems, and Sanmina-SCI Corporation are among the departing dozen.

　　Inclusion in the Nasdaq 100 is good news for those companies and their shareholders because fund managers trying to duplicate the index will be more likely to pick up shares in them. Also, shares from each company are included in the Nasdaq 100 Index Tracking Stock, among the world's most actively traded exchange-traded funds, going by average volume of daily share trading, and the most actively traded listed equity security in the US.