E3 is usually the videogame industry's big party of the year — a chance to celebrate its strengths and showcase the titles it expects to drive sales forward for the rest of the year.

But as the game makers gather for this year's event, a cloud hangs over the soiree. Retail sales are down 27 percent compared to this time in 2011. Mobile devices are stealing the spotlight from traditional consoles. And naysayers are openly questioning the long-term viability of the console industry.