LOS ANGELES -- Sony's press conference, hot on the heels of Nintendo's and a long, smoggy cab ride away, is rolling.

Jack Tretton, top dog at Sony in the U.S., started with some history. Fifteen years ago this week, executives at Sony gave the green light to the original PlayStation. The company was ahead of the technology curve then, introducing gamers to CDs, Tretton said. It's successor, PlayStation 2, was built with a 10-year plan in mind, and has now sold some 140 million units.

LOS ANGELES -- Nintendo has gathered another big crowd of media and game-industry partners inside the Kodak Theater on Hollywood Boulevard this morning for its E3 press conference.

Here are some of the questions hanging over Nintendo, the breakout success story of the current-generation console competition:

LOS ANGELES -- I'll be covering the E3 press conferences of Nintendo and Sony - Microsoft's competitors in the game console business - beginning this morning at 9 and 11:30 a.m., respectively. Meanwhile, here's today's story summarizing Microsoft's games and entertainment announcements from Monday. You can see all of my posts from E3 here.