Making popular video games is something Valve, a 12-year-old Bellevue, WA-based software and tech company, has down cold. Its debut title, Half-Life, has won over 50 Game of the Year Awards, a distinction awarded by various titles and Web sites to a deserving video game. With one of its better-known offerings, Team Fortress 2, the company is displaying equal marketing acumen.

Early this month, Valve seized an opportunity to cement itself as a customer-friendly brand by offering all future downloadable content ...