Two games will have a lock on spring sales

With the arrival in stores this week of long-awaited titles Grand Theft Auto IV and Mario Kart Wii, the already hot video game industry is headed for the stratosphere.

For 24 months in a row, sales of video-game systems and software have grown over the previous year. That performance led to record sales of $18 billion last year, up from $12.5 billion in 2006, according to market tracking firm The NPD Group.

Industry observers were prepared for a breather after the strong 2007 holiday season, but sales continue to rocket. "With continued demand for games like Guitar Hero and Rock Band, big-ticket items, and the (Nintendo) Wii not in stock ... we saw some big numbers in February and March," says Edward Williams, an analyst with BMO Capital Markets.

Sales rose 34% in February ($1.3 billion) and 57% in March ($1.7 billion) over the previous year and ...